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                                 UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                   FORM N-CSR

                   CERTIFIED SHAREHOLDER REPORT OF REGISTERED
                        MANAGEMENT INVESTMENT COMPANIES



		Investment Company Act file number 811-21321

                          Pioneer Municipal High Income Trust
               (Exact name of registrant as specified in charter)


                       60 State Street, Boston, MA 02109
              (Address of principal executive offices) (ZIP code)


            Dorothy E. Bourassa, Pioneer Investment Management, Inc.,
                       60 State Street, Boston, MA 02109
                    (Name and address of agent for service)


Registrant's telephone number, including area code:  (617) 742-7825


Date of fiscal year end:  April 30


Date of reporting period:  May 1, 2008 through April 30, 2009


Form N-CSR is to be used by management investment companies to file reports with
the Commission not later than 10 days after the transmission to stockholders of
any report that is required to be transmitted to stockholders under Rule 30e-1
under the Investment Company Act of 1940 (17 CFR 270.30e-1).  The Commission may
use the information provided on Form N-CSR in its regulatory, disclosure review,
inspection, and policymaking roles.

A registrant is required to disclose the information specified by Form N-CSR,
and the Commission will make this information public. A registrant is not
required to respond to the collection of information contained in Form N-CSR
unless the Form displays a currently valid Office of Management and Budget
("OMB") control number. Please direct comments concerning the accuracy of the
information collection burden estimate and any suggestions for reducing the
burden to Secretary, Securities and Exchange Commission, 450 Fifth Street, NW,
Washington, DC 20549-0609.  The OMB has reviewed this collection of information
under the clearance requirements of 44 U.S.C. ss. 3507.


ITEM 1. REPORTS TO SHAREOWNERS.


Pioneer Municipal High
Income Trust
--------------------------------------------------------------------------------
Annual Report | April 30, 2009
--------------------------------------------------------------------------------

Ticker Symbol:    MHI


[LOGO] PIONEER
       Investments(R)






                        visit us: pioneerinvestments.com


Table of Contents



                                                                          
Letter to Shareowners                                                          2
Portfolio Management Discussion                                                4
Portfolio Summary                                                              8
Prices and Distributions                                                       9
Performance Update                                                            10
Schedule of Investments                                                       11
Financial Statements                                                          20
Financial Highlights                                                          23
Notes to Financial Statements                                                 25
Report of Independent Registered Public Accounting Firm                       32
Approval of Investment Advisory Agreement                                     35
Trustees, Officers and Service Providers                                      38



              Pioneer Municipal High Income Trust | Annual Report | 4/30/09    1


President's Letter


Dear Shareowner,

Stock and bond markets around the globe have been experiencing one of their
most tumultuous periods in history. Investors have witnessed volatility of a
magnitude that many have never before seen. Distance often provides the best
vantage point for perspective. Still, we believe that the benefits of basic
investment principles that have stood the test of time -- even in the midst of
market turmoil -- cannot be underestimated.

First, invest for the long term. The founder of Pioneer Investments, Philip L.
Carret, began his investment career during the 1920s. One lesson he learned is
that while great prosperity affords an advantageous time for selling stocks,
extreme economic slumps can create opportunities for purchase. Indeed, many of
our portfolio managers, who follow the value-conscious investing approach of
our founder, are looking at recent market conditions as an opportunity to buy
companies whose shares we believe have been unjustifiably beaten down by
indiscriminate selling, but that we have identified as having strong prospects
over time. While investors may be facing a sustained market downturn, we
continue to believe that patience, along with staying invested in the market,
are important considerations for long-term investors.

A second principle is to stay diversified across different types of
investments. The global scope of the current market weakness poses challenges
for this basic investment axiom. But the turbulence makes now a good time to
reassess your portfolio and make sure that your investments continue to meet
your needs. We believe you should work closely with your financial advisor to
find the mix of stocks, bonds and money market assets that is best aligned to
your particular risk tolerance and investment objective.

As the investment markets sort through the continuing crisis in the financial
industry, we are staying focused on the fundamentals and risk management. With
more than 80 years of experience behind us, we have learned how to navigate
turbulent markets. At Pioneer Investments, risk management has always been a
critical part of our culture -- not just during periods of extraordinary
volatility. Our investment process is based on fundamental research,
quantitative analysis and active portfolio management. This three-pillared
process, which we apply to each of our portfolios, is supported by an
integrated team approach and is designed to carefully balance risk and reward.
While we


2    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


see potential chances for making money in many corners of the market, it takes
research and experience to separate solid investment opportunities from
speculation.

We invite you to learn more about Pioneer and our time-tested approach to
investing by consulting with your financial advisor or visiting us online at
www.pioneerinvestments.com. Thank you for investing with Pioneer.

Sincerely,





/s/ Daniel K. Kingsbury

Daniel K. Kingsbury
President and CEO
Pioneer Investment Management USA Inc.


Any information in this shareowner report regarding market or economic trends
or the factors influencing the Trust's historical or future performance are
statements of the opinion of Trust management as of the date of this report.
These statements should not be relied upon for any other purposes. Past
performance is no guarantee of future results, and there is no guarantee that
market forecasts discussed will be realized.


              Pioneer Municipal High Income Trust | Annual Report | 4/30/09    3


Portfolio Management Discussion | 4/30/09

In the following interview, David Eurkus, who is responsible for the daily
management of the Pioneer Municipal High Income Trust, discusses some of the
factors that had an impact on the municipal bond market and the Trust over the
12-month period ended April 30, 2009.

Q  How did the Trust perform over the 12 months ended April 30, 2009?

A  For the 12-month period ended April 30, 2009, Pioneer Municipal High Income
   Trust produced a total return of -13.94% at net asset value and -18.85% at
   market price. As of April 30, 2009, the Trust was selling at a discount of
   market price to net asset value of -7.0%. The Barclays Capital (formerly
   Lehman Brothers) Municipal Bond Index, which tracks the performance of
   investment-grade bonds, returned 3.11% for the same 12 months ended April
   30, 2009, while the Barclays Capital High Yield Municipal Bond Index
   returned -17.71%. The indices are not leveraged. While the Trust invested
   in municipal securities with a broad range of maturities and credit
   ratings, it maintained a dollar-weighted average portfolio credit quality
   of A- as of April 30, 2009. At the end of the 12 months ended April 30,
   2009, the Trust held 116 issues in 37 states, territories and the District
   of Columbia. The Trust's 30-day SEC yield was 10.87% and the distribution
   rate, based on the market close on April 30, 2009 was 8.65%, based on the
   most recent monthly dividend.

Q  What was the investment environment like during the 12-month period ended
   April 30, 2009?

A  It was an environment of substantial market unrest, as the credit crisis led
   to one of the most volatile and illiquid periods in the history of the
   fixed-income markets. The seizing up of the credit markets, the bankruptcy
   of Lehman Brothers, the AIG fiasco, and the mergers of Merrill Lynch with
   Bank of America and Bear Stearns with JPMorgan Chase were just some of the
   events that led to the great disruption in the financial markets. In this
   environment, the municipal bond market saw liquidity dry up, new issuance
   come to a halt, forced selling by several financial institutions and a huge
   number of redemptions as investors fled to the safety of the Treasury
   market. As a result of this turmoil, municipal bond yields rose to historic
   levels above Treasury yields. Never in history has the ratio of municipal
   bond yields to Treasury yields been so high. Typically, the 30-year rate of
   municipal yields to Treasury yields has been approximately 90%. In December
   2008, the ratio increased to over 200%. During the first four months of
   2009, the municipal bond market rebounded. There was improvement in


4    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


   liquidity, and municipal bond yields declined, although they remained above
   Treasury yields.

Q  What factors affected the Trust's performance during the 12-month period
   ended April 30, 2009?

A  The Trust's performance was affected by defaults in some of its holdings,
   including: exposure to Lehman Brothers through a municipal bond issued by
   Main Street Natural Gas in Georgia; a position in the Las Vegas Monorail
   System; and the default of the St. Louis Convention Center. The Trust's
   position in airline/airport bonds also held back returns. Despite the steep
   decline in fuel prices, airline/airport bonds lost value, reflecting
   concerns that airline/airport revenues would continue to contract in the
   weak global economy. In the final weeks of the 12-month period, we saw a
   modest upturn in the value of airline/airport bonds. Some of the Trust's
   hospital bonds, which are rated A/Baa, also dampened performance, as their
   long duration in a rising interest-rate environment had a negative impact
   during the final quarter of 2008.

   The Trust's return at net asset value trailed the Barclays Capital
   Municipal Bond Index by a significant margin, partially due to the effects
   of the Trust's strategy to use leverage, or borrowed funds, to invest. This
   is a normal part of our investment strategy. We obtain financing by issuing
   auction rate preferred shares, which is a low-cost way of borrowing money.
   Leverage tends to exaggerate performance both when the market is producing
   positive returns and when it is producing negative returns. During the
   Trust's fiscal year, the use of leverage exacerbated the effects of the
   declining prices of high-yield bonds.

   Because of the crisis in the credit markets, the market for auction rate
   preferred shares was frozen over the 12 months ended April 30, 2009. That
   made it difficult for investors holding auction rate preferred shares to
   sell their shares, and it increased the borrowing costs incurred by the
   Trust because of the terms outlined by the documents authorizing issuance
   of preferred shares. At the end of the fiscal year, the Trust's leverage
   ratio was 28.9%, an increase from the 24.5% level at the start of the
   12-month period on May 1, 2008.While the amount of borrowed funds had not
   increased, the declining values of the bonds in the Trust's portfolio
   increased the proportion of leverage.

   While the Trust had a setback over the past 12 months, its portfolio is
   comprised of what we believe are solid investments that should weather the
   problems in the economy and financial markets. As always has been the case
   at Pioneer, our investment decisions are based on a value-oriented, risk-
   managed investment approach that uses a bottom-up security selection
   process and top-down economic and market analysis.


              Pioneer Municipal High Income Trust | Annual Report | 4/30/09    5


Q  How did you manage the Trust during the 12-month period ended April 30, 2009?


A  We made no material changes to the Trust's portfolio and maintained an
   emphasis on sectors that underpin the U.S. economy. Some of the Trust's
   sector positions included health care (31.3% of the total investment
   portfolio), tobacco bonds (11.9% of the total investment portfolio),
   airport revenue (10.7% of the total investment portfolio), pollution
   control bonds (4.6% of the total investment portfolio), facilities revenue
   (4.3% of the total investment portfolio) and transportation revenue (4.0%
   of the total investment portfolio).

   In terms of credit quality, at April 30, 2009, 44.3% of the Trust's total
   investment portfolio was invested in investment-grade bonds, and 55.7% of
   the total investment portfolio was invested in below-investment-grade
   bonds.

Q  What is your outlook?

A  The municipal bond market has begun to recover from the turmoil of the past
   12 months. Investors are returning to the market, and we have seen prices
   increase and yields decline. Over the first four months of the year, as of
   April 30, 2009, the Barclays Capital Municipal Bond Index and the Barclays
   Capital High Yield Municipal Bond Index rose by 6.31% and 10.00%,
   respectively.

   As we look ahead, we believe the municipal market should continue to be
   attractive as states and municipalities receive Federal government stimulus
   money that can be used for infrastructure repair, education and health care
   programs. We are monitoring closely developments in Washington regarding
   the health care sector. "Build America Bonds" are also part of the
   government's stimulus. Under this program, the U.S. Treasury will subsidize
   35% of issuers' net interest costs. We believe this program will result in
   a large amount of new issuance of taxable municipal debt and a reduction in
   the new issuance of tax-exempt debt. This could be positive for tax-exempt
   municipal bonds. At a time when tax rates are likely to rise, we expect to
   see demand increase and supply contract. This supply/demand dynamic could
   increase the value of tax-exempt municipal bonds.

Please refer to the Schedule of Investments on pages 11-19 for a full listing
of Trust securities.

Investments in high-yield or lower-rated securities are subject to
greater-than-average risk. The Trust may invest in securities of issuers that
are in default or that are in bankruptcy.

A portion of income may be subject to state, federal, and/or alternative
minimum tax. Capital gains, if any, are subject to a capital gains tax. When
interest rates rise, the prices of fixed-income securities held by the Trust
will generally fall. Conversely, when interest rates fall the prices of
fixed-income securities held by the


6    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Trust generally will rise. By concentrating in municipal securities, the Trust
is more susceptible to adverse economic, political or regulatory developments
than is a portfolio that invests more broadly. Investments in the Trust are
subject to possible loss due to the financial failure of underlying securities
and their inability to meet their debt obligations.

The Trust uses leverage through the issuance of preferred shares with an
aggregate liquidation preference of up to 25% of the Trust's total assets after
such issuance. Leverage creates significant risks, including the risk that the
Trust's income or capital appreciation will not be sufficient to cover the cost
of leverage, which may adversely affect the return for the holders of common
shares.

The Trust is required to maintain certain regulatory and rating agency asset
coverage requirements in connection with its outstanding preferred shares. In
order to maintain required asset coverage levels, the Trust may be required to
alter the composition of its investment portfolio or take other actions, such
as redeeming preferred shares with the proceeds from portfolio transactions, at
what might be inopportune times in the market. Such actions could reduce the
net earnings or returns to holders of the Trust's common shares over time.

Risks of investing in the Trust are discussed in greater detail in the Trust's
original offering prospectus relating to its common shares.

Past performance is no guarantee of future results, and there is no guarantee
that market forecasts discussed will be realized.

Any information in this shareowner report regarding market or economic trends
or the factors influencing the Trust's historical or future performance are
statements of the opinion of Trust management as of the date of this report.
These statements should not be relied upon for any other purposes.


              Pioneer Municipal High Income Trust | Annual Report | 4/30/09    7


Portfolio Summary | 4/30/09

Portfolio Diversification
--------------------------------------------------------------------------------
(As a percentage of total investment portfolio)


[THE FOLLOWING DATA WAS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL]


                                                                        
Health Revenue                                                             31.3%
Other Revenue                                                              12.9%
Tobacco Revenue                                                            11.9%
Airport Revenue                                                            10.7%
Insured                                                                    10.6%
Pollution Control Revenue                                                   4.6%
Facilities Revenue                                                          4.3%
Transportation Revenue                                                      4.0%
Education Revenue                                                           3.7%
Development Revenue                                                         3.6%
Utilities Revenue                                                           1.0%
Gaming Revenue                                                              0.7%
Airline Revenue                                                             0.4%
Housing Revenue                                                             0.3%



Portfolio Quality
--------------------------------------------------------------------------------
(As a percentage of total investment portfolio; based on S&P ratings)


[THE FOLLOWING DATA WAS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL]


                                                                        
AAA                                                                        20.2%
AA                                                                          3.5%
A                                                                           3.0%
BBB                                                                        17.6%
BB                                                                          3.2%
B                                                                           7.4%
CCC                                                                         1.7%
Not Rated                                                                  43.4%





10 Largest Holdings
------------------------------------------------------------------------------------------------------------------------------------
(As a percentage of long-term holdings)*
                                                                                                                         
    1.             Allegheny County Hospital Development Authority Revenue, 9.25%, 11/15/30                                    4.12%
------------------------------------------------------------------------------------------------------------------------------------
    2.             Metropolitan Pier & Exposition Authority Dedicated State Tax Revenue, 0.0%, 6/15/22                         3.67
------------------------------------------------------------------------------------------------------------------------------------
    3.             Tobacco Settlement Financing Corp., 6.75%, 6/1/39                                                           3.51
------------------------------------------------------------------------------------------------------------------------------------
    4.             Connecticut Health & Educational Facilities Authority Revenue, RIB, 12.542%,
                   7/1/42 (144A)                                                                                               3.25
------------------------------------------------------------------------------------------------------------------------------------
    5.             North Texas Tollway Authority Revenue, 5.75%, 1/1/33                                                        2.77
------------------------------------------------------------------------------------------------------------------------------------
    6.             New Jersey Economic Development Authority Revenue, 6.25%, 9/15/29                                           2.53
------------------------------------------------------------------------------------------------------------------------------------
    7.             New York State Dormitory Authority Revenue, RIB, 14.095%, 7/1/26 (144A)                                     2.50
------------------------------------------------------------------------------------------------------------------------------------
    8.             Golden State Tobacco Securitization Corp., 7.875%, 6/1/42                                                   2.48
------------------------------------------------------------------------------------------------------------------------------------
    9.             Johnson City Health & Educational Facilities Board Hospital Revenue, 7.5%, 7/1/33                           2.33
------------------------------------------------------------------------------------------------------------------------------------
   10.             Washington State General Obligation, 0.0%, 6/1/22                                                           2.30
------------------------------------------------------------------------------------------------------------------------------------


* This list excludes temporary cash. The Trust is actively managed, and
  currently holdings may be different. The holdings listed should not be
  considered recommendations to buy or sell any security listed.


8    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Prices and Distributions | 4/30/09




Market Value per Common Share
--------------------------------------------------------------------------------

             4/30/09         4/30/08
--------------------------------------------------------------------------------
                        
           $ 10.40         $ 13.88
--------------------------------------------------------------------------------





Net Asset Value per Common Share
--------------------------------------------------------------------------------

             4/30/09         4/30/08
--------------------------------------------------------------------------------
                        
           $ 11.18         $ 14.07
--------------------------------------------------------------------------------






Distributions per Common Share: 5/1/08-4/30/09
--------------------------------------------------------------------------------

            Net
         Investment        Short-Term         Long-Term
           Income        Capital Gains      Capital Gains
--------------------------------------------------------------------------------
                                        
          $ 0.8500          $ --              $ --
--------------------------------------------------------------------------------




              Pioneer Municipal High Income Trust | Annual Report | 4/30/09    9


Performance Update | 4/30/09

Investment Returns
--------------------------------------------------------------------------------
The mountain chart on the right shows the change in market value, including
reinvestment of dividends and distributions, of a $10,000 investment made in
common shares of Pioneer Municipal High Income Trust, compared to that of the
Barclays Capital Municipal Bond Index and Barclays Capital High Yield Municipal
Bond Index.




Cumulative Total Returns
(As of April 30, 2009)
--------------------------------------------------------------------------------
                                      Net Asset                  Market
Period                                Value ("NAV")              Price
--------------------------------------------------------------------------------
                                                           
 Life-of-Class
 (7/17/2003)                              14.25%                   1.53%
 5 Years                                   5.66                    5.89
 1 Year                                  -13.94                  -18.85
--------------------------------------------------------------------------------


[THE FOLLOWING DATA WAS REPRESENTED AS A LINE/MTN CHART IN THE PRINTED MATERIAL]



Value of $10,000 Investment
--------------------------------------------------------------------------------
                                               Barclays                Barclays
                       Pioneer              Capital High                Capital
                    Municipal High         Yield Municipal             Municipal
                     Income Trust             Bond Index              Bond Index*
--------------------------------------------------------------------------------
                                                               
8/03                    10000                   10000                   10000
4/04                    10813                   10441                    9895
4/05                    12399                   11153                   10202
4/06                    12794                   11394                   10047
4/07                    14265                   12052                   10056
4/08                    13275                   12388                   10039
4/09                    10153                   12773                   10218

* Index comparison begins July 31, 2003


Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent
month-end performance results. Current performance may be lower or higher than
the performance data quoted.

Performance data shown represents past performance. Past performance is no
guarantee of future results. Investment return and market price will fluctuate,
and your shares may trade below net asset value ("NAV") due to such factors as
interest rate changes and the perceived credit quality of borrowers.

Total investment return does not reflect broker sales charges or commissions.
All performance is for common shares of the Trust.

Closed-end funds, unlike open-end funds, are not continuously offered. There is
a one-time public offering and once issued, shares of closed-end funds are sold
in the open market through a stock exchange and frequently trade at prices
lower than their NAV. NAV is total assets less total liabilities which includes
preferred shares, divided by the number of common shares outstanding.

When NAV is lower than market price, dividends are assumed to be reinvested at
the greater of NAV or 95% of the market price. When NAV is higher, dividends
are assumed to be reinvested at prices obtained under the Trust's dividend
reinvestment plan.

The performance table and graph do not reflect the deduction of fees and taxes
that a shareowner would pay on Trust distributions or the sale of Trust shares.

The Barclays Capital Municipal Bond Index is a broad measure of the municipal
bond market. The Barclays Capital High Yield Municipal Bond Index totals over
$26 billion in market value and maintains over 1300 securities. Municipal bonds
in this index have the following requirements: maturities of one year or
greater, sub investment grade (below Baa or non-rated), fixed coupon rate,
issued after 12/31/90, deal size over $20 million, and maturity size of at
least $3 million. Index returns are calculated monthly, assume reinvestment of
dividends and, unlike Trust returns, do not reflect any fees, expenses or sales
charges. The indices are not leveraged. You cannot invest directly in the
indices.


10    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Schedule of Investments | 4/30/09




-----------------------------------------------------------------------------------------------------
                   S&P/Moody's
Principal          Ratings
Amount             (unaudited)                                                          Value
-----------------------------------------------------------------------------------------------------
                                                                               
                                 TAX EXEMPT OBLIGATIONS -- 134.9% of Net Assets
                                 Alabama -- 0.7%
  $   1,000,000           NR/NR  Huntsville-Redstone Village Special Care Facilities
                                 Financing Authority, 5.5%, 1/1/28                       $    662,220
      2,000,000           NR/NR  Huntsville-Redstone Village Special Care Facilities
                                 Financing Authority, 5.5%, 1/1/43                          1,166,940
                                                                                         ------------
                                                                                         $  1,829,160
-----------------------------------------------------------------------------------------------------
                                 Arizona -- 2.2%
      5,000,000       BBB-/Baa3  Apache County Industrial Development Authority,
                                 5.85%, 3/1/28                                           $  4,459,750
        970,000         NR/Baa3  Pima County Industrial Development Authority,
                                 7.25%, 7/1/31                                                721,845
        500,000         NR/Baa2  Yavapai County Industrial Development Authority,
                                 6.0%, 8/1/33                                                 394,465
                                                                                         ------------
                                                                                         $  5,576,060
-----------------------------------------------------------------------------------------------------
                                 California -- 12.3%
      2,425,000            A/A2  California State, 5.75%, 4/1/31                         $  2,467,049
      7,885,000(a)       AAA/NR  California State University Revenue, RIB, 10.858%,
                                 11/1/39 (144A)                                             7,464,256
      4,500,000           NR/NR  California Statewide Communities Development
                                 Authority Environmental Facilities Revenue,
                                 9.0%, 12/1/38                                              3,532,455
      1,000,000          BB+/NR  California Statewide Communities Development
                                 Authority Revenue, 7.25%, 10/1/38                            769,050
      5,150,000+        AAA/Aaa  Golden State Tobacco Securitization Corp.,
                                 7.8%, 6/1/42                                               6,220,273
      7,000,000+        AAA/Aaa  Golden State Tobacco Securitization Corp.,
                                 7.875%, 6/1/42                                             8,474,130
      1,000,000          AA/Aa1  University of California Revenue, 5.0%, 5/15/25            1,017,900
        655,000            C/NR  Valley Health System Hospital Revenue,
                                 6.5%, 5/15/25                                                414,418
                                                                                         ------------
                                                                                         $ 30,359,531
-----------------------------------------------------------------------------------------------------
                                 Connecticut -- 5.5%
     10,335,000(a)       NR/Aaa  Connecticut Health & Educational Facilities Authority
                                 Revenue, RIB, 12.542%, 7/1/42 (144A)                    $ 11,121,287
      5,000,000           B+/NR  Mohegan Tribe Indians Gaming Authority,
                                 6.25%, 1/1/31                                              2,500,150
                                                                                         ------------
                                                                                         $ 13,621,437
-----------------------------------------------------------------------------------------------------
                                 Delaware -- 0.4%
        765,000           NR/NR  Sussex County Delaware Revenue, 5.9%, 1/1/26            $    555,864
        600,000           NR/NR  Sussex County Delaware Revenue, 6.0%, 1/1/35                 387,600
                                                                                         ------------
                                                                                         $    943,464
-----------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    11


Schedule of Investments | 4/30/09   (continued)



---------------------------------------------------------------------------------------------------
                   S&P/Moody's
Principal          Ratings
Amount             (unaudited)                                                        Value
---------------------------------------------------------------------------------------------------
                                                                             
                                 District of Columbia -- 3.4%
  $  5,000,000         BBB/Baa3  District of Columbia Tobacco Settlement Financing
                                 Corp., 6.5%, 5/15/33                                  $  3,817,600
     6,000,000         BBB/Baa3  District of Columbia Tobacco Settlement Financing
                                 Corp., 6.75%, 5/15/40                                    4,647,360
                                                                                       ------------
                                                                                       $  8,464,960
---------------------------------------------------------------------------------------------------
                                 Florida -- 5.3%
     1,700,000            NR/NR  Beacon Lakes Community Development,
                                 6.9%, 5/1/35                                          $  1,211,131
     2,000,000            A-/A3  Brevard County Health Facilities Authority Revenue,
                                 5.0%, 4/1/36                                             1,539,840
     2,500,000            NR/NR  Liberty County Subordinate Revenue,
                                 8.25%, 7/1/28                                            2,062,800
     2,500,000            A-/A2  Miami-Dade County Aviation Revenue,
                                 5.5%, 10/1/41                                            2,370,250
     1,000,000            NR/NR  St. Johns County Industrial Development Authority
                                 Revenue, 5.25%, 1/1/26                                     650,780
     2,000,000            NR/NR  St. Johns County Industrial Development Authority
                                 Revenue, 5.375%, 1/1/40                                  1,129,480
     5,000,000          NR/Baa2  Tallahassee Health Facilities Revenue,
                                 6.375%, 12/1/30                                          4,220,150
                                                                                       ------------
                                                                                       $ 13,184,431
---------------------------------------------------------------------------------------------------
                                 Georgia -- 3.0%
     4,240,000(a)        NR/Aa3  Atlanta Georgia Water & Waste Revenue, RIB,
                                 7.682%, 11/1/43 (144A)                                $  3,779,366
     2,400,000            NR/NR  Fulton County Residential Care Facilities Revenue,
                                 5.0%, 7/1/27                                             1,493,880
     2,600,000            NR/NR  Fulton County Residential Care Facilities Revenue,
                                 5.125%, 7/1/42                                           1,403,376
     1,000,000            NR/NR  Rockdale County Development Authority Revenue,
                                 6.125%, 1/1/34                                             663,890
                                                                                       ------------
                                                                                       $  7,340,512
---------------------------------------------------------------------------------------------------
                                 Guam -- 1.5%
     5,000,000            NR/NR  Northern Mariana Islands, 5.0%, 10/1/22               $  3,614,550
---------------------------------------------------------------------------------------------------
                                 Idaho -- 1.7%
     5,000,000         BBB/Baa2  Power County Industrial Development Corp.,
                                 6.45%, 8/1/32                                         $  4,313,250
---------------------------------------------------------------------------------------------------
                                 Illinois -- 8.5%
     2,000,000(b)         NR/NR  Centerpoint Intermodal Center, 10.0%,
                                 6/15/23 (144A)                                        $  1,564,120
     1,000,000            NR/NR  Illinois Finance Authority Revenue, 6.0%, 11/15/27         696,780
     2,000,000          AA+/Aa2  Illinois Finance Authority Revenue, 6.0%, 8/15/39        2,041,340
     4,000,000            NR/NR  Illinois Finance Authority Revenue, 6.0%, 11/15/39       2,391,000
---------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

12    Pioneer Municipal High Income Trust | Annual Report | 4/30/09





-----------------------------------------------------------------------------------------------------
                     S&P/Moody's
Principal            Ratings
Amount               (unaudited)                                                        Value
-----------------------------------------------------------------------------------------------------
                                                                               
                                   Illinois -- (continued)
   $   1,500,000(c)         NR/NR  Illinois Health Facilities Authority Revenue,
                                   6.9%, 11/15/33                                        $    661,350
      16,880,000(d)        AAA/A2  Metropolitan Pier & Exposition Authority Dedicated
                                   State Tax Revenue, 0.0%, 6/15/22                        12,566,316
       1,800,000            NR/NR  Southwestern Illinois Development Authority
                                   Revenue, 5.625%, 11/1/26                                 1,170,090
                                                                                         ------------
                                                                                         $ 21,090,996
-----------------------------------------------------------------------------------------------------
                                   Indiana -- 4.6%
       5,000,000            A+/A2  Indiana Health & Educational Facility Financing
                                   Authority Hospital Revenue, 5.0%, 2/15/39             $  3,820,450
       1,000,000        BBB+/Baa1  Indiana State Development Finance Authority
                                   Revenue, 5.6%, 12/1/32                                     839,400
       4,300,000          BBB+/NR  Indiana State Development Finance Authority
                                   Revenue, 5.75%, 10/1/11                                  4,105,081
       2,500,000(b)      BBB/Baa2  Rockport Pollution Control Revenue, 6.25%, 6/1/25        2,558,725
                                                                                         ------------
                                                                                         $ 11,323,656
-----------------------------------------------------------------------------------------------------
                                   Louisiana -- 1.9%
       1,500,000          BB+/Ba3  Louisiana Local Government Environmental Facilities
                                   Revenue, 6.75%, 11/1/32                               $  1,044,075
       5,000,000            NR/A3  Louisiana Public Facilities Authority Revenue,
                                   5.5%, 5/15/47                                            3,706,800
                                                                                         ------------
                                                                                         $  4,750,875
-----------------------------------------------------------------------------------------------------
                                   Massachusetts -- 4.1%
       2,440,000            NR/NR  Massachusetts Development Finance Agency
                                   Revenue, 7.1%, 7/1/32                                 $  1,883,826
       3,500,000         BBB/Baa3  Massachusetts Health & Educational Facilities
                                   Authority Revenue, 6.25%, 7/1/22                         3,070,970
       2,500,000            NR/NR  Massachusetts Health & Educational Facilities
                                   Authority Revenue, 6.5%, 1/15/38                         1,656,150
       5,000,000           BB-/NR  Massachusetts Health & Educational Facilities
                                   Authority Revenue, 6.75%, 10/1/33                        3,629,300
                                                                                         ------------
                                                                                         $ 10,240,246
-----------------------------------------------------------------------------------------------------
                                   Michigan -- 2.2%
         950,000            NR/NR  Doctor Charles Drew Academy, 5.7%, 11/1/36            $    518,443
       1,700,000           NR/Ba1  Flint Michigan Hospital Building Authority Revenue,
                                   5.25%, 7/1/16                                            1,400,069
       1,500,000            BB/NR  John Tolfree Health System Corp., 6.0%, 9/15/23          1,129,050
       2,000,000          BB-/Ba3  Michigan State Hospital Finance Authority Revenue,
                                   5.5%, 8/15/23                                            1,326,220
       1,470,000           BBB/NR  Star International Academy Certificates of
                                   Participation, 6.125%, 3/1/37                            1,057,783
                                                                                         ------------
                                                                                         $  5,431,565
-----------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    13


Schedule of Investments | 4/30/09   (continued)




----------------------------------------------------------------------------------------------------
                   S&P/Moody's
Principal          Ratings
Amount             (unaudited)                                                         Value
----------------------------------------------------------------------------------------------------
                                                                              
                                 Minnesota -- 0.6%
  $  1,675,000           BB-/NR  Duluth Economic Development Authority Health Care
                                 Facilities Revenue, 7.25%, 6/15/32                     $  1,363,400
----------------------------------------------------------------------------------------------------
                                 Mississippi -- 1.1%
     3,000,000          BBB/Ba1  Mississippi Business Finance Corp. Pollution Control
                                 Revenue, 5.9%, 5/1/22                                  $  2,745,180
----------------------------------------------------------------------------------------------------
                                 Montana -- 0.1%
     1,600,000(c)         NR/NR  Two Rivers Authority, Inc. Correctional Facility
                                 Improvement Revenue, 7.375%, 11/1/27                   $    312,096
----------------------------------------------------------------------------------------------------
                                 Nebraska -- 0.5%
     2,000,000            NR/NR  Grand Island Solid Waste Disposal Facilities
                                 Revenue, 7.0%, 6/1/23                                  $  1,369,980
----------------------------------------------------------------------------------------------------
                                 Nevada -- 0.1%
     2,000,000            NR/NR  Nevada State Department of Business & Industry,
                                 7.25%, 1/1/23                                          $    140,000
----------------------------------------------------------------------------------------------------
                                 New Jersey -- 10.9%
     2,000,000             B/B3  New Jersey Economic Development Authority
                                 Revenue, 6.25%, 9/15/19                                $  1,460,020
    13,350,000             B/B3  New Jersey Economic Development Authority
                                 Revenue, 6.25%, 9/15/29                                   8,653,470
     1,000,000             B/B3  New Jersey Economic Development Authority
                                 Revenue, 6.4%, 9/15/23                                      688,350
     6,150,000(b)          B/B3  New Jersey Economic Development Authority
                                 Revenue, 7.0%, 11/15/30                                   4,286,612
    10,000,000+         AAA/Aaa  Tobacco Settlement Financing Corp.,
                                 6.75%, 6/1/39                                            12,014,500
                                                                                        ------------
                                                                                        $ 27,102,952
----------------------------------------------------------------------------------------------------
                                 New Mexico -- 1.3%
     1,500,000            NR/NR  Otero County New Mexico Project Revenue,
                                 6.0%, 4/1/23                                           $  1,131,915
     2,960,000            NR/NR  Otero County New Mexico Project Revenue,
                                 6.0%, 4/1/28                                              2,119,982
                                                                                        ------------
                                                                                        $  3,251,897
----------------------------------------------------------------------------------------------------
                                 New York -- 10.9%
     2,500,000        BBB+/Baa2  Albany New York Industrial Development Agency
                                 Civic Facilities Revenue, 5.25%, 11/15/27              $  2,036,025
     3,000,000            NR/NR  Dutchess County Industrial Development Agency
                                 Revenue, 7.5%, 3/1/29                                     2,690,580
     2,000,000            NR/NR  Nassau County New York Industrial Development
                                 Agency Revenue, 6.7%, 1/1/43                              1,479,940
     2,000,000          NR/Baa1  New York City Industrial Development Agency,
                                 5.375%, 6/1/23                                            1,670,740
----------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

14    Pioneer Municipal High Income Trust | Annual Report | 4/30/09





-----------------------------------------------------------------------------------------------------
                    S&P/Moody's
Principal           Ratings
Amount              (unaudited)                                                          Value
-----------------------------------------------------------------------------------------------------
                                                                               
                                  New York -- (continued)
  $  12,990,000        CCC+/Caa2  New York City Industrial Development Agency,
                                  6.9%, 8/1/24                                           $  5,001,280
      7,040,000(a)        NR/Aaa  New York State Dormitory Authority Revenue, RIB,
                                  14.095%, 7/1/26 (144A)                                    8,551,136
      2,000,000            NR/NR  Suffolk County Industrial Development Agency,
                                  7.25%, 1/1/30                                             1,586,480
      4,000,000          AA-/Aa3  Triborough Bridge & Tunnel Authority Revenue,
                                  5.25%, 11/15/30                                           4,053,040
                                                                                         ------------
                                                                                         $ 27,069,221
-----------------------------------------------------------------------------------------------------
                                  North Carolina -- 2.7%
      4,530,000            NR/NR  Charlotte North Carolina Special Facilities Revenue,
                                  5.6%, 7/1/27                                           $  2,576,936
      5,740,000            NR/NR  Charlotte North Carolina Special Facilities Revenue,
                                  7.75%, 2/1/28                                             4,063,289
                                                                                         ------------
                                                                                         $  6,640,225
-----------------------------------------------------------------------------------------------------
                                  Oklahoma -- 5.3%
      1,000,000+         AAA/Aaa  Oklahoma Development Finance Authority Revenue,
                                  5.625%, 8/15/19                                        $  1,023,510
      7,000,000+         AAA/Aaa  Oklahoma Development Finance Authority Revenue,
                                  5.625%, 8/15/29                                           7,164,570
      1,225,000          B-/Caa2  Tulsa Municipal Airport Revenue, 6.25%, 6/1/20              869,566
      4,350,000          B-/Caa2  Tulsa Municipal Airport Revenue, 7.35%, 12/1/11           3,980,250
                                                                                         ------------
                                                                                         $ 13,037,896
-----------------------------------------------------------------------------------------------------
                                  Pennsylvania -- 9.4%
      3,000,000           BB/Ba3  Allegheny County Hospital Development Authority
                                  Revenue, 5.0%, 11/15/28                                $  1,639,560
      1,550,000          NR/Baa2  Allegheny County Hospital Development Authority
                                  Revenue, 5.125%, 5/1/25                                   1,232,312
     12,300,000+          AAA/NR  Allegheny County Hospital Development Authority
                                  Revenue, 9.25%, 11/15/30                                 14,088,666
      1,000,000            B-/NR  Columbia County Hospital Authority Health Care
                                  Revenue, 5.9%, 6/1/29                                       676,380
        925,000          BBB/Ba2  Hazleton Health Services Authority Hospital Revenue,
                                  5.625%, 7/1/17                                              740,962
      1,280,000            NR/B3  Langhorne Manor Borough Higher Education &
                                  Health Authority Revenue, 7.35%, 7/1/22                     907,597
      3,900,000           NR/Ba3  Pennsylvania Economic Development Financing
                                  Authority Revenue, 6.75%, 12/1/36                         3,587,883
        500,000          BBB+/NR  Pennsylvania Higher Educational Facilities Authority
                                  Revenue, 5.4%, 7/15/36                                      397,660
                                                                                         ------------
                                                                                         $ 23,271,020
-----------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    15


Schedule of Investments | 4/30/09   (continued)



----------------------------------------------------------------------------------------------------
                   S&P/Moody's
Principal          Ratings
Amount             (unaudited)                                                         Value
----------------------------------------------------------------------------------------------------
                                                                              
                                 Rhode Island -- 1.7%
  $  6,000,000            NR/NR  Central Falls Detention Facilities Revenue,
                                 7.25%, 7/15/35                                         $  4,110,120
----------------------------------------------------------------------------------------------------
                                 South Carolina -- 2.8%
     5,185,000+       BBB+/Baa1  South Carolina Jobs Economic Development
                                 Authority Revenue, 6.375%, 8/1/34                      $  6,069,872
       665,000+       BBB+/Baa1  South Carolina Jobs Economic Development
                                 Authority Revenue, 6.375%, 8/1/34                           771,147
                                                                                        ------------
                                                                                        $  6,841,019
----------------------------------------------------------------------------------------------------
                                 Tennessee -- 5.4%
     7,000,000+           NR/A2  Johnson City Health & Educational Facilities Board
                                 Hospital Revenue, 7.5%, 7/1/33                         $  7,964,950
     2,480,000            NR/A1  Knox County Health, Educational & Housing Facilities
                                 Board Hospital Revenue, 6.375%, 4/15/22                   2,515,737
     4,600,000          BBB+/NR  Sullivan County Health, Educational & Housing
                                 Facilities Board Hospital Revenue,
                                 5.25%, 9/1/36                                             2,790,314
                                                                                        ------------
                                                                                        $ 13,271,001
----------------------------------------------------------------------------------------------------
                                 Texas -- 14.8%
     1,345,000           NR/Ba2  Bexar County Housing Finance Corp.,
                                 8.0%, 12/1/36                                          $    965,011
     1,000,000        CCC+/Caa2  Dallas-Fort Worth International Airport Revenue,
                                 6.0%, 11/1/14                                               485,010
     4,000,000            NR/NR  Decatur Hospital Authority Revenue, 7.0%, 9/1/25          3,222,720
     2,000,000            NR/NR  Gulf Coast Industrial Development Authority
                                 Revenue, 7.0%, 12/1/36                                      885,020
     3,750,000            B-/B3  Houston Airport System Special Facilities Revenue,
                                 5.7%, 7/15/29                                             2,199,975
     5,340,000            NR/NR  Lubbock Health Facilities Development Corp.,
                                 6.625%, 7/1/36                                            3,728,228
    10,000,000          BBB+/A3  North Texas Tollway Authority Revenue,
                                 5.75%, 1/1/33                                             9,491,800
     2,810,000(a)        NR/Aa2  Northside Independent School District, RIB,
                                 12.325%, 6/15/33 (144A)                                   2,962,976
       500,000         CCC/Caa2  Sabine River Authority Pollution Control Revenue,
                                 6.15%, 8/1/22                                               200,355
     7,040,000(a)        NR/Aa1  Texas State, RIB, 13.248%, 4/1/30 (144A)                  7,501,402
     1,075,000            NR/NR  Willacy County Local Government Corp. Revenue,
                                 6.0%, 9/1/10                                              1,042,825
     5,250,000            NR/NR  Willacy County Local Government Corp. Revenue,
                                 6.875%, 9/1/28                                            3,907,890
                                                                                        ------------
                                                                                        $ 36,593,212
----------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

16    Pioneer Municipal High Income Trust | Annual Report | 4/30/09





------------------------------------------------------------------------------------------------------------
                          S&P/Moody's
Principal                 Ratings
Amount                    (unaudited)                                                       Value
                                                                                   
------------------------------------------------------------------------------------------------------------
                                        Utah -- 0.2%
    $      800,000               NR/NR  Spanish Fork City Charter School Revenue, 5.55%,
                                        11/15/26 (144A)                                       $      556,064
------------------------------------------------------------------------------------------------------------
                                        Vermont -- 0.6%
         1,500,000               A-/A3  Vermont Educational & Health Buildings Financing
                                        Agency Revenue, 6.0%, 10/1/28                         $    1,544,970
------------------------------------------------------------------------------------------------------------
                                        Virginia -- 0.4%
         1,000,000            BBB/Baa2  Peninsula Ports Authority, 6.0%, 4/1/33               $      880,430
------------------------------------------------------------------------------------------------------------
                                        Washington -- 8.7%
         4,710,000              AA-/A2  Spokane Public Facilities District Hotel/Motel Tax
                                        & Sales, 5.75%, 12/1/27                               $    4,884,788
         7,025,000            BBB/Baa3  Tobacco Settlement Authority Revenue,
                                        6.625%, 6/1/32                                             5,583,400
        14,315,000             AA+/Aa1  Washington State General Obligation, 0.0%, 6/1/22          7,866,236
         5,000,000               NR/NR  Washington State Housing Finance Committee
                                        Nonprofit Revenue, 5.625%, 1/1/27                          3,278,200
                                                                                              --------------
                                                                                              $   21,612,624
------------------------------------------------------------------------------------------------------------
                                        Wisconsin -- 0.1%
         2,320,000               NR/NR  Aztalan Wisconsin Exempt Facilities Revenue,
                                        7.5%, 5/1/18                                          $      132,240
------------------------------------------------------------------------------------------------------------
                                        TOTAL TAX-EXEMPT OBLIGATIONS
                                        (Cost $378,068,301)                                   $  333,930,240
------------------------------------------------------------------------------------------------------------
                                        MUNICIPAL COLLATERALIZED DEBT OBLIGATION -- 2.7%
                                        of Net Assets
        10,000,000(b)(e)         NR/NR  Non-Profit Preferred Funding Trust I,12.0%,
                                        9/15/37 (144A)                                        $    6,670,400
------------------------------------------------------------------------------------------------------------
                                        TOTAL MUNICIPAL COLLATERALIZED DEBT
                                        OBLIGATION
                                        (Cost $10,000,000)                                    $    6,670,400
------------------------------------------------------------------------------------------------------------
       Shares
------------------------------------------------------------------------------------------------------------
                                        COMMON STOCK -- 0.6% of Net Assets
           247,994(f)                   Delta Air Lines, Inc.                                 $    1,530,123
------------------------------------------------------------------------------------------------------------
                                        TOTAL COMMON STOCK
                                        (Cost $6,612,756)                                     $    1,530,123
------------------------------------------------------------------------------------------------------------
                                        TOTAL INVESTMENTS IN SECURITIES -- 138.2%
                                        (Cost $394,681,057)(g)(h)                             $  342,130,763
------------------------------------------------------------------------------------------------------------
                                        OTHER ASSETS AND LIABILITIES -- 2.6%                  $    6,432,675
------------------------------------------------------------------------------------------------------------
                                        PREFERRED SHARES AT REDEMPTION VALUE,
                                        INCLUDING DIVIDENDS PAYABLE -- (40.8)%                $ (101,003,430)
------------------------------------------------------------------------------------------------------------
                                        NET ASSETS APPLICABLE TO COMMON
                                        SHAREOWNERS -- 100.0%                                 $  247,560,008
------------------------------------------------------------------------------------------------------------

The accompanying notes are an integral part of these financial statements.

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    17


Schedule of Investments | 4/30/09   (continued)

RIB     Residual Interest Bonds

NR      Security not rated by S&P or Moody's.

(144A)  Security is exempt from registration under Rule 144A of the Securities
        Act of 1933. Such securities may be resold normally to qualified
        institutional buyers in a transaction exempt from registration. At April
        30, 2009 the value of these securities amounted to $50,171,007 or 20.3%
        of net assets applicable to common shareowners.

+       Prerefunded bonds have been collateralized by U.S. Treasury securities
        or U.S. Government Agencies which are held in escrow to pay interest and
        principal on the tax exempt issue and to retire the bonds in full at the
        earliest refunding date.

(a)     The interest rate is subject to change periodically and inversely based
        upon prevailing market rates. The interest rate shown is the coupon rate
        at April 30, 2009.

(b)     The interest rate is subject to change periodically. The interest rate
        shown is the coupon rate at April 30, 2009.

(c)     Security is in default and is non-income producing.

(d)     Debt obligation initially issued at one coupon which converts to a
        higher coupon at a specific date. The rate shown is the coupon rate at
        April 30, 2009.

(e)     Indicates a security that has been deemed illiquid. The aggregate cost
        of illiquid securities is $10,000,000. The aggregate value $6,670,400
        represents 2.7% of the net assets.

(f)     Non-income producing.

(g)     The concentration of investments by type of obligation/market sector is
        as follows (unaudited):


                                                    
             Insured:
               NATL-RE                                  7.4%
               FSA                                      1.1
               ACA                                      0.9
               PSF                                      0.9
               AMBAC                                    0.3
             Revenue Bonds:
               Health Revenue                          31.4
               Other Revenue                           12.9
               Tobacco Revenue                         12.0
               Airport Revenue                         10.8
               Pollution Control Revenue                4.6
               Facilities Revenue                       4.3
               Transportation Revenue                   4.0
               Education Revenue                        3.7
               Development Revenue                      3.7
               Utilities Revenue                        1.0
               Gaming Revenue                           0.7
               Housing Revenue                          0.3
                                                      -----
                                                      100.0%
                                                      =====


The accompanying notes are an integral part of these financial statements.

18    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


(h)     At January 31, 2009, the net unrealized loss on investments based on
        cost for federal income tax purposes of $392,778,850 was as follows:


                                                                                  
         Aggregate gross unrealized gain for all investments in which there is an
           excess of value over tax cost                                             $ 18,463,823
         Aggregate gross unrealized loss for all investments in which there is an
           excess of tax cost over value                                              (69,111,910)
                                                                                     ------------
         Net unrealized loss                                                         $(50,648,087)
                                                                                     ============


For financial reporting purposes net unrealized loss on investments was
$52,550,294 and cost of investments aggregated $394,681,057.

Purchases and sales of securities (excluding temporary cash investments) for
the year ended April 30, 2009, aggregated $56,253,960 and $56,236,117,
respectively.

Various inputs are used in determining the value of the Trust's investments.
These inputs are summarized in the three broad levels listed below.

Highest priority is given to Level 1 inputs and lowest priority is given to
Level 3.

  Level 1  --  quoted prices in active markets for identical securities

  Level 2  --  other significant observable inputs (including quoted prices
               for similar securities, interest rates, prepayment speeds, credit
               risk, etc.)

  Level 3  --  significant unobservable inputs (including the Trust's own
               assumptions in determining fair value of investments)

The following is a summary of the inputs used as of April 30, 2009, in valuing
the Trust's investments:



--------------------------------------------------------------------------------
                                                                Investments
 Valuation Inputs                                               in Securities
--------------------------------------------------------------------------------
                                                             
 Level 1 -- Quoted Prices                                       $  1,530,123
 Level 2 -- Other Significant Observable Inputs                  340,600,640
 Level 3 -- Significant Unobservable Inputs                               --
--------------------------------------------------------------------------------
 Total                                                          $342,130,763
================================================================================


The accompanying notes are an integral part of these financial statements.

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    19


Statement of Assets and Liabilities | 4/30/09



                                                                                                                  
ASSETS:
  Investments in securities, at value (cost $394,681,057)                                                             $ 342,130,763
  Cash                                                                                                                      347,811
  Receivables --
   Investment securities sold                                                                                               100,000
   Interest                                                                                                               8,664,032
  Prepaid expenses                                                                                                           32,533
------------------------------------------------------------------------------------------------------------------------------------
     Total assets                                                                                                     $ 351,275,139
------------------------------------------------------------------------------------------------------------------------------------
LIABILITIES:
  Payables --
   Investments securities purchased                                                                                   $   2,415,575
  Due to affiliates                                                                                                         180,456
  Administration fee payable                                                                                                 19,737
  Accrued expenses                                                                                                           95,933
------------------------------------------------------------------------------------------------------------------------------------
     Total liabilities                                                                                                $   2,711,701
------------------------------------------------------------------------------------------------------------------------------------
PREFERRED SHARES AT REDEMPTION VALUE:
  $25,000 liquidation value per share applicable to 4,040 shares,
   including dividends payable of $3,430                                                                              $ 101,003,430
------------------------------------------------------------------------------------------------------------------------------------
NET ASSETS APPLICABLE TO COMMON SHAREOWNERS:
  Paid-in capital                                                                                                     $ 315,434,908
  Undistributed net investment income                                                                                     7,400,424
  Accumulated net realized loss on investments and interest rate swaps                                                  (22,725,030)
  Net unrealized loss on investments                                                                                    (52,550,294)
------------------------------------------------------------------------------------------------------------------------------------
     Net assets applicable to common shareowners                                                                      $ 247,560,008
------------------------------------------------------------------------------------------------------------------------------------
NET ASSET VALUE PER SHARE:
  No par value, (unlimited number of shares authorized)
  Based on $247,560,008/22,140,525 common shares                                                                      $       11.18
====================================================================================================================================


The accompanying notes are an integral part of these financial statements.

20    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Statement of Operations

For the Year Ended 4/30/09




                                                                                                                 
INVESTMENT INCOME:
  Interest                                                                                                             $ 27,967,270
------------------------------------------------------------------------------------------------------------------------------------
EXPENSES:
  Management fees                                                                   $    2,196,502
  Administration fees                                                                      359,742
  Transfer agent fees and expenses                                                          38,031
  Auction agent fees                                                                       267,789
  Custodian fees                                                                            59,027
  Registration fees                                                                         23,819
  Professional fees                                                                        124,039
  Printing expense                                                                          23,717
  Trustees' fees                                                                            13,990
  Pricing fees                                                                              19,113
  Miscellaneous                                                                             33,773
------------------------------------------------------------------------------------------------------------------------------------
     Total expenses                                                                                                    $  3,159,542
------------------------------------------------------------------------------------------------------------------------------------
       Net investment income                                                                                           $ 24,807,728
------------------------------------------------------------------------------------------------------------------------------------
REALIZED AND UNREALIZED GAIN (LOSS) ON
INVESTMENTS AND INTEREST RATE SWAPS:
  Net realized loss from:
   Investments                                                                      $   (5,927,111)
   Interest rate swaps                                                                    (462,743)                    $ (6,389,854)
------------------------------------------------------------------------------------------------------------------------------------
  Change in net unrealized gain (loss) from:
   Investments                                                                      $  (61,172,082)
   Interest rate swaps                                                                     250,905                     $(60,921,177)
------------------------------------------------------------------------------------------------------------------------------------
     Net loss on investments and interest rate swaps                                                                   $(67,311,031)
------------------------------------------------------------------------------------------------------------------------------------
DISTRIBUTIONS TO PREFERRED SHAREOWNERS FROM
NET INVESTMENT                                                                                                         $ (2,525,210)
------------------------------------------------------------------------------------------------------------------------------------
  Net decrease in net assets applicable to common shareowners
   resulting from operations                                                                                           $(45,028,513)
====================================================================================================================================


The accompanying notes are an integral part of these financial statements.

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    21


Statement of Changes in Net Assets

For the Years Ended 4/30/09 and 4/30/08, respectively



                                                                                                   Year                   Year
                                                                                                   Ended                  Ended
                                                                                                  4/30/09                4/30/08
                                                                                                                
FROM OPERATIONS:
Net investment income                                                                         $  24,807,728           $  23,933,484
Net realized loss on investments and interest rate swaps                                         (6,389,854)             (2,753,968)
Change in net unrealized gain (loss) on investments and interest
  rate swaps                                                                                    (60,921,177)            (42,308,635)
Distributions to preferred shareowners from net investment
  income                                                                                         (2,525,210)             (3,773,609)
------------------------------------------------------------------------------------------------------------------------------------
     Net decrease in net assets applicable to common
       shareowners resulting from operations                                                  $ (45,028,513)          $ (24,902,728)
------------------------------------------------------------------------------------------------------------------------------------
DISTRIBUTIONS TO COMMON SHAREOWNERS:
($0.85 and $0.83 per share, respectively)                                                     $ (18,817,657)          $ (18,449,784)
------------------------------------------------------------------------------------------------------------------------------------
     Total distributions to common shareowners                                                $ (18,817,657)          $ (18,449,784)
------------------------------------------------------------------------------------------------------------------------------------
FROM TRUST SHARE TRANSACTIONS:
Reinvestment of distributions                                                                 $     175,511           $      96,845
------------------------------------------------------------------------------------------------------------------------------------
   Net increase in net assets applicable to common
     shareowners resulting from Trust share transactions                                      $     175,511           $      96,845
------------------------------------------------------------------------------------------------------------------------------------
   Net decrease in net assets applicable to common
     shareowners                                                                              $ (63,670,659)          $ (43,255,667)
NET ASSETS APPLICABLE TO COMMON SHAREOWNERS:
Beginning of year                                                                               311,230,667             354,486,334
------------------------------------------------------------------------------------------------------------------------------------
End of year                                                                                   $ 247,560,008           $ 311,230,667
------------------------------------------------------------------------------------------------------------------------------------
Undistributed net investment income                                                           $   7,400,424           $   4,413,468
------------------------------------------------------------------------------------------------------------------------------------


The accompanying notes are an integral part of these financial statements.

22    Pioneer Municipal High Income Trust | Annual Report | 4/30/09



Financial Highlights


------------------------------------------------------------------------------------------------------------------------------------
                                                                         Year        Year         Year         Year         Year
                                                                        Ended       Ended        Ended        Ended        Ended
                                                                       4/30/09     4/30/08      4/30/07      4/30/06      4/30/05
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                           
Per Common Share Operating Performance
Net asset value, beginning of period                                  $  14.07     $ 16.02      $ 15.15      $ 15.62      $ 14.76
------------------------------------------------------------------------------------------------------------------------------------
Increase (decrease) from investment operations:(a)
 Net investment income                                                $   1.12     $  1.08      $  1.02      $  1.02      $  1.14
 Net realized and unrealized gain (loss) on investments and
  interest rate swaps                                                    (3.05)      (2.03)        0.78        (0.48)        0.95
 Dividends and distributions to preferred shareowners from:
  Net investment income                                                  (0.11)      (0.17)       (0.16)       (0.12)       (0.07)
  Net realized gains                                                        --          --           --           --         0.00(b)
------------------------------------------------------------------------------------------------------------------------------------
 Net increase (decrease) from investment operations                   $  (2.04)    $ (1.12)     $  1.64      $  0.42      $  2.02
Dividends and distributions to common shareowners from:
 Net investment income                                                   (0.85)      (0.83)       (0.77)       (0.89)       (1.07)
 Net realized gains                                                         --          --           --          --         (0.09)
Capital charge with respect to issuance of:
 Common shares                                                              --          --           --          --          0.00(b)
------------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net asset value                            $  (2.89)    $ (1.95)     $  0.87      $ (0.47)     $  0.86
------------------------------------------------------------------------------------------------------------------------------------
Net asset value, end of period(c)                                     $  11.18     $ 14.07      $ 16.02      $ 15.15      $ 15.62
------------------------------------------------------------------------------------------------------------------------------------
Market value, end of period(c)                                        $  10.40     $ 13.88      $ 15.05      $ 13.22      $ 14.33
====================================================================================================================================
Total return at market value(d)                                         (18.85)%     (2.28)%       20.04%      (1.85)%      13.34%
Ratios to average net assets of common shareowners
 Net expenses(e)                                                          1.19%       1.03%         1.06%       1.03%        1.04%
 Net investment income before preferred share dividends                   9.36%       7.17%         6.49%       6.64%        7.60%
 Preferred share dividends                                                0.95%       1.13%         1.01%       0.80%        0.43%
 Net investment income available to common shareowners                    8.41%       6.04%         5.48%       5.84%        7.17%



The accompanying notes are an integral part of these financial statements.

               Pioneer Municipal High Income Trust | Annual Report | 4/30/09  23



Financial Highlights (continued)


------------------------------------------------------------------------------------------------------------------------------------
                                                                   Year           Year            Year          Year          Year
                                                                  Ended          Ended           Ended         Ended         Ended
                                                                 4/30/09        4/30/08         4/30/07       4/30/06       4/30/05
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                           
Portfolio turnover                                                     16%           17%             18%           20%           25%
Net assets of common shareowners, end of period
 (in thousands)                                                 $ 247,560     $ 311,231       $ 354,486     $ 335,121     $ 345,555
Preferred shares outstanding (in thousands)                     $ 101,000     $ 101,000       $ 101,000     $ 101,000     $ 101,000
Asset coverage per preferred share, end of period(f)            $  86,278     $ 102,047       $ 112,759     $ 107,962     $ 110,533
Average market value per preferred share                        $  25,000     $  25,000       $  25,000     $  25,000     $  25,000
Liquidation value, including dividends payable, per
 preferred share                                                $  25,001     $  25,010       $  25,014     $  25,011     $  25,000
Ratios to average net assets of common shareowners before
 waivers and reimbursement of expenses
 Net expenses(e)                                                     1.19%         1.03%           1.06%         1.03%         1.04%
 Net investment income before preferred share dividends              9.36%         7.17%           6.49%         6.64%         7.60%
 Preferred share dividends                                           0.95%         1.13%           1.01%         0.80%         0.43%
 Net investment income available to common shareowners               8.41%         6.04%           5.48%         5.84%         7.17%
====================================================================================================================================


(a)  The per common share data presented above is based upon the average common
     shares outstanding for the periods presented.

(b)  Amount is less than $0.01 per share.

(c)  Net asset value and market value are published in Barron's on Saturday, The
     Wall Street Journal on Monday and The New York Times on Monday and
     Saturday.

(d)  Total investment return is calculated assuming a purchase of common shares
     at the current market value on the first day and a sale at the current
     market value on the last day of the periods reported. Dividends and
     distributions, if any, are assumed for purposes of this calculation to be
     reinvested at prices obtained under the Trust's dividend reinvestment plan.
     Total investment return does not reflect brokerage commissions. Past
     performance is not a guarantee of future results.

(e)  Expense ratios do not reflect the effect of dividend payments to preferred
     shareowners.

(f)  Market value is redemption value without an active market.


     The information above represents the audited operating performance data for
     a common share outstanding, total investment return, ratios to average net
     assets and other supplemental data for the periods indicated. This
     information has been determined based upon financial information provided
     in the financial statements and market value data for the Trust's common
     shares. The accompanying notes are an integral part of these financial
     statements.

The accompanying notes are an integral part of these financial statements.

24  Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Notes to Financial Statements | 4/30/09


1. Organization and Significant Accounting Policies

Pioneer Municipal High Income Trust (the "Trust") was organized as a Delaware
statutory trust on March 13, 2003. Prior to commencing operations on July 21,
2003, the Trust had no operations other than matters relating to its
organization and registration as a diversified, closed-end management
investment company under the Investment Company Act of 1940, as amended. The
primary investment objective of the Trust is to seek a high level of current
income exempt from regular federal income tax and, as a secondary objective,
the Trust may seek capital appreciation to the extent consistent with its
primary investment objective.

The Trust may invest in both investment and below investment grade (high-yield)
municipal securities with a broad range of maturities and credit ratings. Debt
securities rated below investment grade are commonly referred to as "junk
bonds" and are considered speculative. These securities involve greater risk of
loss, are subject to greater price volatility, and are less liquid, especially
during periods of economic uncertainty or change, than higher rated debt
securities.

Information regarding the Trust's principal risks is contained in the Trust's
original offering prospectus with additional information included in the
Trust's shareowner reports from time to time. Please refer to those documents
when considering the Trust's investment risks. At times, the Trust's
investments may represent industries or industry sectors that are interrelated
or have common risks, making it more susceptible to any economic, political, or
regulatory developments or other risks affecting those industries and sectors.

The Trust's financial statements have been prepared in conformity with U.S.
generally accepted accounting principles that require the management of the
Trust to, among other things, make estimates and assumptions that affect the
reported amounts of assets and liabilities, and the reported amounts of income,
expenses and gains and losses on investments during the reporting year. Actual
results could differ from those estimates.

The following is a summary of significant accounting policies followed by the
Trust in the preparation of its financial statements, which are consistent with
those policies generally accepted in the investment company industry:


             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    25


A. Security Valuation

   Security transactions are recorded as of trade date. Securities are valued at
   prices supplied by independent pricing services, which consider such factors
   as Treasury spreads, yields, maturities and ratings. Valuations may be
   supplemented by values obtained from dealers and other sources, as required.
   The values of interest rate swaps are determined by obtaining dealer
   quotations. Securities for which there are no other readily available
   valuation methods are valued using fair value methods pursuant to procedures
   adopted by the Board of Trustees ("board determined"). The Trust may also use
   fair value methods to value a security including a non-U.S. security, when
   the closing market price on the principal exchange where the security is
   traded no longer reflects the value of the security. At April 30, 2009, there
   were no securities that were board determined.

   Dividend income is recorded on the ex-dividend date, except that certain
   dividends from foreign securities where the ex-dividend date may have passed
   are recorded as soon as the Trust becomes aware of the ex-dividend data in
   the exercise of reasonable diligence. Discount and premium on debt securities
   are accreted or amortized, respectively, daily on an effective yield to
   maturity basis and are included in interest income. Interest income,
   including interest bearing cash accounts, is recorded on an accrual basis.

   Gains and losses on sales of investments are calculated on the identified
   cost method for both financial reporting and federal income tax purposes.


B. Federal Income Taxes

   It is the Trust's policy to comply with the requirements of the Internal
   Revenue Code applicable to regulated investment companies and to distribute
   all of its taxable income and net realized capital gains, if any, to its
   shareowners. Therefore, no federal income tax provision is required. Tax
   years for the prior three fiscal years remain subject to examination by tax
   authorities.

   The amounts and characterizations of distributions to shareowners for
   financial reporting purposes are determined in accordance with federal income
   tax rules. Therefore, the sources of the Trust's distributions may be shown
   in the accompanying financial statements as from or in excess of net
   investment income or as from net realized gain (loss) on investment
   transactions, or as from paid in-capital, depending on the type of book/tax
   differences that may exist.

   At April 30, 2009, the Trust reclassified $477,905 to decrease undistributed
   net investment income and decrease net realized loss on investments to
   reflect permanent book/tax differences. The reclassification has no impact on
   the net asset value of the Trust and presents the Trust's capital accounts on
   a tax basis.


26    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


   At April 30, 2009, the Trust had a net capital loss carryforward of
   $15,079,753 which is comprised of $6,354,842 which will expire in 2014,
   $4,138,757 which will expire in 2015 and $4,586,154 which will expire in
   2017, if not utilized.

   The Trust has elected to defer approximately $7,564,631 in capital losses
   realized between November 1, 2008 and April 30, 2009 to its fiscal year
   ending April 30, 2010.

   The tax character of distributions paid to common and preferred shareowners
   during the years ended April 30, 2009 and April 30, 2008 were as follows:





--------------------------------------------------------------------------------
                                                          2009              2008
--------------------------------------------------------------------------------
                                                               
   Distributions paid from:
   Tax exempt income                               $21,171,440       $21,567,992
   Ordinary income                                     171,427           655,401
--------------------------------------------------------------------------------
     Total                                         $21,342,867       $22,223,393
--------------------------------------------------------------------------------


  The following shows the components of distributable earnings on a federal
  income tax basis at April 30, 2009.




--------------------------------------------------------------------------------
                                                                           2009
--------------------------------------------------------------------------------
                                                               
   Distributable earnings:
   Undistributed tax-exempt income                                $   5,302,103
   Undistributed ordinary income                                        118,898
   Capital loss carryforward                                        (15,079,753)
   Post-October loss deferred                                        (7,564,631)
   Dividend payable                                                      (3,430)
   Unrealized depreciation                                          (50,648,087)
--------------------------------------------------------------------------------
     Total                                                        $ (67,874,900)
--------------------------------------------------------------------------------


   The difference between book-basis and tax-basis unrealized depreciation is
   primarily attributable to the difference between book and tax amortization
   methods for premiums and discounts on fixed income securities, book/tax
   difference in the accrual of income on securities in default and other
   temporary differences.


C. Automatic Dividend Reinvestment Plan

   All common shareowners automatically participate in the Automatic Dividend
   Reinvestment Plan (the "Plan"), under which participants receive all
   dividends and capital gain distributions (collectively, "dividends") in full
   and fractional common shares of the Trust in lieu of cash. Shareowners may
   elect not to participate in the Plan. Shareowners not participating in the
   Plan receive all dividends and capital gain distributions in cash.
   Participation in the Plan is completely voluntary and may be terminated or
   resumed at any time without penalty by notifying American Stock Transfer &
   Trust


             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    27


   Company, the agent for shareowners in administering the Plan (the "Plan
   Agent"), in writing prior to any dividend record date; otherwise such
   termination or resumption will be effective with respect to any subsequently
   declared dividend or other distribution.

   Whenever the Trust declares a dividend on common shares payable in cash,
   participants in the Plan will receive the equivalent in common shares
   acquired by the Plan Agent either (i) through receipt of additional unissued
   but authorized common shares from the Trust or (ii) by purchase of
   outstanding common shares on the New York Stock Exchange or elsewhere. If, on
   the payment date for any dividend, the net asset value per common share is
   equal to or less than the market price per share plus estimated brokerage
   trading fees ("market premium"), the Plan Agent will invest the dividend
   amount in newly issued common shares. The number of newly issued common
   shares to be credited to each account will be determined by dividing the
   dollar amount of the dividend by the net asset value per common share on the
   date the shares are issued, provided that the maximum discount from the then
   current market price per share on the date of issuance does not exceed 5%.
   If, on the payment date for any dividend, the net asset value per common
   share is greater than the market value ("market discount"), the Plan Agent
   will invest the dividend amount in common shares acquired in open-market
   purchases. There are no brokerage charges with respect to newly issued common
   shares.

   However, each participant will pay a pro rata share of brokerage trading fees
   incurred with respect to the Plan Agent's open-market purchases.
   Participating in the Plan does not relieve shareowners from any federal,
   state or local taxes which may be due on dividends paid in any taxable year.
   Shareowners holding Plan shares in a brokerage account may not be able to
   transfer the shares to another broker and continue to participate in the
   Plan.


2. Management Agreement

Pioneer Investment Management, Inc. ("PIM"), a wholly owned indirect subsidiary
of UniCredit S.p.A. ("UniCredit"), manages the Trust's portfolio. Management
fees payable under the Trust's Advisory Agreement with PIM are calculated daily
at the annual rate of 0.60% of the Trust's average daily managed assets.
"Managed Assets" means the total assets of the Trust (including any assets
attributable to any leverage that may be outstanding) minus the sum of accrued
liabilities (other than debt representing financial leverage). For the year
ended April 30, 2009, the net management fee was equivalent to 0.60% of the
Trust's average daily managed assets, which was equivalent to 0.83% of the
Trust's average daily net assets attributable to the common shareowners.

In addition, under PIM's management and administration agreements, certain
other services and costs are paid by PIM and reimbursed by the Trust. At April
30, 2009, $180,456 was payable to PIM related to management costs,


28    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


administrative costs and certain other services and is included in "Due to
Affiliates" on the Statement of Assets and Liabilities.

The Trust has retained Princeton Administrators, LLC ("Princeton") to provide
certain administrative and accounting services to the Trust on its behalf. The
Trust pays Princeton a monthly fee at an annual rate of 0.07% of the average
daily value of the Trust's managed assets up to $500 million and 0.03% of
average daily managed assets in excess of $500 million, subject to a minimum
monthly fee of $10,000.


3. Transfer Agents

Pioneer Investment Management Shareholder Services, Inc. ("PIMSS"), a wholly
owned indirect subsidiary of UniCredit, through a sub-transfer agency agreement
with American Stock Transfer & Trust Company, provides substantially all
transfer agent and shareowner services related to the Trust's common shares at
negotiated rates. Deutsche Bank Trust Company Americas ("Deutsche Bank") is the
transfer agent, registrar, dividend paying agent and auction agent with respect
to the Trust's Auction Preferred Shares ("APS"). The Trust pays Deutsche Bank
an annual fee, as is agreed to from time to time by the Trust and Deutsche
Bank, for providing such services.


4. Interest Rate Swaps

The Trust may enter into interest rate swap transactions to attempt to protect
itself from increasing dividend or interest expense on its leverage resulting
from increasing short-term interest rates. The cost of leverage may rise with
an increase in interest rates, generally having the effect of lower yields and
potentially lower dividends to common shareowners. Interest rate swaps can be
used to "lock in" the cost of leverage and reduce the negative impact that
rising short-term interest rates would have on the Trust's leveraging costs.

An interest rate swap is an agreement between two parties, which involves
exchanging a floating rate and fixed rate interest payments for a specified
period of time. Interest rate swaps involve the accrual of the net interest
payments between the parties on a daily basis, with the net amount recorded
within the unrealized appreciation/depreciation of interest rate swaps on the
Statement of Assets and Liabilities. Once the interim payments are settled in
cash, at the pre-determined dates specified in the agreement, the net amount is
recorded as realized gain or loss from interest rate swaps on the Statement of
Operations. During the term of the swap, changes in the value of the swap are
recognized as unrealized gains and losses by "marking-to-market" the value of
the swap based on values obtained from dealer quotations. When the swap is
terminated, the Trust will record a realized gain or loss equal to the
difference, if any, between the proceeds from (or cost of) closing the contract
and the cost basis of the contract. The Trust is exposed to credit risk in the
event of non-performance by the other party to the interest rate swap. Risk may
also arise

             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    29


with regard to market movements in the value of the swap arrangement that do
not exactly offset the changes in the related dividend requirement or interest
expense on the Trust's leverage.

There were no interest rate swap contracts outstanding at April 30, 2009.


5. Trust Shares

There are an unlimited number of common shares of beneficial interest
authorized.

Transactions in common shares of beneficial interest for the years ended April
30, 2009 and April 30, 2008 were as follows:





--------------------------------------------------------------------------------
                                                             2009           2008
--------------------------------------------------------------------------------
                                                                
Shares outstanding at beginning of year                22,127,742     22,120,893
Reinvestment of distributions                              12,783          6,849
--------------------------------------------------------------------------------
Shares outstanding at end of year                      22,140,525     22,127,742
================================================================================


The Trust may classify or reclassify any unissued common shares of beneficial
interest into one or more series of preferred shares of beneficial interest. As
of April 30, 2009, there were 4,040 APS as follows: Series A-2,000 and Series
B-2,040.

Dividends on Series A and Series B are cumulative at a rate which is reset
every seven days based on the results of an auction. An auction fails if there
are more APS offered for sale than there are buyers. When an auction fails, the
dividend rate for the period will be the maximum rate on the auction dates
described in the prospectus for the APS. Preferred shareowners will not be able
to sell their APS at an auction if the auction fails. Since February 2008, the
Trust's auctions related to the APS have failed. The maximum rate for the 7-Day
Series is 110% of the 7 day commercial rate or Kenny rate. Dividend rates
ranged from 0.594% to 12.565% during the year ended April 30, 2009.

The Trust may not declare dividends or make other distributions on its common
shares or purchase any such shares if, at the time of the declaration,
distribution or purchase, the Trust does not comply with the asset coverage
ratios described in the prospectus for the APS.

The APS are redeemable at the option of the Trust, in whole or in part, on any
dividend payment date at $25,000 per share plus any accumulated or unpaid
dividends, whether or not declared. The APS are also subject to mandatory
redemption at $25,000 per share plus any accumulated or unpaid dividends,
whether or not declared, if certain requirements relating to the composition of
the assets and liabilities of the Trust as set forth in the Statement of
Preferences are not satisfied.


30    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


The holders of APS have voting rights equal to the holders of the Trust's
common shares (one vote per share) and will vote together with holders of the
common shares as a single class. Holders of APS are also entitled to elect two
of the Trust's Trustees. In addition, the Investment Company Act of 1940, as
amended, requires that along with approval by shareowners that might otherwise
be required, the approval of the holders of a majority of any outstanding
preferred shares, voting separately as a class, would be required to (a) adopt
any plan of reorganization that would adversely affect the preferred shares and
(b) take any action requiring a vote of security holders, including, among
other things, changes in the Trust's subclassification as a closed-end
management investment company or changes in its fundamental investment
restrictions.


6. New Pronouncement

In March 2008, Statement of Financial Accounting Standards No. 161, Disclosures
about Derivative Instruments and Hedging Activities ("SFAS 161"), was issued
and is effective for fiscal years beginning after November 15, 2008. SFAS 161
requires enhanced disclosures about an entity's derivative and hedging
activities. Management currently is evaluating the impact the adoption of SFAS
161 will have on the Trust's financial statement disclosures.


7. Subsequent Events

Subsequent to April 30, 2009, the Board of Trustees of the Trust declared a
dividend from undistributed net investment income of $0.075 per common share
payable May 29, 2009, to shareowners of record on May 15, 2009.

Subsequent to April 30, 2009, dividends declared and paid on preferred shares
totaled $50,608 in aggregate for the two outstanding preferred share series
through June 4, 2009.


             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    31


Report of Independent Registered Public Accounting Firm


To the Board of Trustees and the Shareowners of
Pioneer Municipal High Income Trust:
--------------------------------------------------------------------------------
We have audited the accompanying statement of assets and liabilities of Pioneer
Municipal High Income Trust (the "Trust"), including the schedule of
investments, as of April 30, 2009, and the related statement of operations for
the year then ended, the statements of changes in net assets for each of the
two years in the period then ended, and the financial highlights for each of
the five years in the period then ended. These financial statements and
financial highlights are the responsibility of the Trust's management. Our
responsibility is to express an opinion on these financial statements and
financial highlights based on our audits.

We conducted our audits in accordance with the standards of the Public Company
Accounting Oversight Board (United States). Those standards require that we
plan and perform the audit to obtain reasonable assurance about whether the
financial statements and financial highlights are free of material
misstatement. We were not engaged to perform an audit of the Trust's internal
control over financial reporting. Our audits included consideration of internal
control over financial reporting as a basis for designing audit procedures that
are appropriate in the circumstances, but not for the purpose of expressing an
opinion on the effectiveness of the Trust's internal control over financial
reporting. Accordingly, we express no such opinion. An audit also includes
examining, on a test basis, evidence supporting the amounts and disclosures in
the financial statements and financial highlights, assessing the accounting
principles used and significant estimates made by management, and evaluating
the overall financial statement presentation. Our procedures included
confirmation of securities owned as of April 30, 2009, by correspondence with
the custodian and brokers or by other appropriate auditing procedures where
replies from brokers were not received. We believe that our audits provide a
reasonable basis for our opinion.

In our opinion, the financial statements and financial highlights referred to
above present fairly, in all material respects, the financial position of
Pioneer Municipal High Income Trust at April 30, 2009, the results of its
operations for the year then ended, the changes in its net assets for each of
the two years in the period then ended, and the financial highlights for each
of the five years in the period then ended, in conformity with U.S. generally
accepted accounting principles.


                                                        /s/ Ernst & Young LLP


Boston, Massachusetts
June 23, 2009


32    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


ADDITIONAL INFORMATION (unaudited)

During the period, there were no material changes in the Trust's investment
objective or fundamental policies that have not been approved by the share-
owners. There have been no changes in the Trust's charter or By-Laws that would
delay or prevent a change in control of the Trust that have not been approved
by the shareowners. There have been no changes in the principle risk factors
associated with investment in the Trust. Day-to-day management of the Trust's
portfolio is the responsibility of David Eurkus. Mr. Eurkus is supported by the
fixed income team. Members of this team manage other Pioneer funds investing
primarily in fixed income securities. The portfolio manager and the team also
may draw upon the research and investment management expertise of Pioneer's
affiliate, Pioneer Investment Management Limited. Mr. Eurkus joined Pioneer as
a senior vice president in January 2000 and has been an investment professional
since 1969.

Notice is hereby given in accordance with Section 23(c) of the Investment
Company Act of 1940 that the Trust may purchase, from time to time, its common
shares in the open market.


Additional Information Regarding the Trust's Investment Policies (unaudited)

On May 7, 2008, the Board of Trustees of the Trust approved certain changes to
the Trust's investment policy with respect to investment by the Trust in
municipal securities rated below investment grade at the time of acquisition.
Effective May 7, 2008, no more than 60% of the Trust's portfolio of municipal
securities will be rated below investment grade at the time of acquisition
(that is, "Ba" or lower by Moody's Investors Services, Inc. ("Moody's") or "BB"
or lower by Standard & Poor's Rating Group ("S&P") or, if unrated, determined
by PIM to be of comparable credit quality). Prior to May 7, 2008, no more than
50% of the Trust's portfolio of municipal securities could be rated below
investment grade at the time of acquisition. In addition, the Trust's policy of
maintaining a dollar-weighted average credit rating of at least investment
grade has been eliminated to allow for utilization of the new 60% policy.
Consistent with the new 60% policy, at least 40% of the Trust's portfolio of
municipal securities will be rated investment grade at the time of acquisition
(that is, at least "Baa" by Moody's or "BBB" by S&P) or, if unrated, determined
by the Trust's investment adviser to be of comparable credit quality.

PIM believes that a higher exposure to below investment grade municipal
securities, upon careful consideration of the risks that these securities may
present, may enable the Trust to capitalize on the yield advantage of the lower
rated municipal securities over higher rated securities in current and future
environments and thereby enhance the Trust's income potential and overall
performance. This change may align the Trust more closely with its peers from
an income perspective over time.


             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    33


CEO CERTIFICATION DISCLOSURE (unaudited)

The Trust's Chief Executive Officer has submitted to the New York Stock
Exchange the annual CEO certification as required by Section 303A.12(a) of the
NYSE Listed Company Manual. In addition, the Trust has filed with the
Securities and Exchange Commission the certification of its Chief Executive
Officer and Chief Financial Officer required by Section 302 of the Sarbanes-
Oxley Act.


Results of Shareholder Meeting (unaudited)

On September 22, 2008, Pioneer Municipal High Income Trust held its annual
meeting of shareowners to elect Class II Trustees. All Class II Trustees were
elected. Below are the detailed results of the votes.

Proposal 1 -- To elect Class II Trustees.



--------------------------------------------------------------------------------
 Nominee                             For              Withheld         Abstained
--------------------------------------------------------------------------------
                                                              
 Benjamin M. Friedman                21,209,198       0                340,524
 Margaret B.W. Graham                21,209,161       0                340,561
 Daniel K. Kingsbury                 21,210,803       0                338,919



IMPORTANT TAX INFORMATION (unaudited)

The following summarizes the taxable per share distributions paid by Pioneer
Municipal High Income Trust during the taxable year ended April 30, 2009:



--------------------------------------------------------------------------------
                                    Payable                    Ordinary
                                    Date                       Income
--------------------------------------------------------------------------------
                                                         
 Common Shareowners                 12/19/2008                 $ 0.006417
 Preferred Shareowners
  Series A                          12/17/2008                 $    7.26

  Series B                          12/18/2008                 $    6.39
  Series B                          12/26/2008                 $    0.88



All of the other net investment income distributions paid by the Trust qualify
as tax-exempt interest dividends for federal income tax purposes.


34    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Approval of Investment Advisory Agreement (unaudited)


Pioneer Investment Management, Inc. (PIM) serves as the Trust's investment
adviser pursuant to an investment advisory agreement between PIM and the Trust.
The Trustees of the Trust, as required by law, determine annually whether to
continue the investment advisory agreement for the Trust.

The contract renewal process began in March 2008 as the Trustees of the Trust
agreed on, among other things, an overall approach and timeline for the
process. In July, the Trustees approved the format of the contract renewal
materials and submitted their formal request to PIM to furnish information
necessary to evaluate the terms of the investment advisory agreement. The
contract renewal materials were provided to the Trustees in August. After
reviewing and discussing the materials, the Trustees submitted a request for
additional information to PIM in September, and materials were provided in
response to this request later that month. Meetings of the Independent Trustees
of the Trust were held in September and October to review and discuss the
contract renewal materials.

At a meeting held on November 11, 2008, based on their evaluation of the
information provided by PIM, the Trustees of the Trust, including the
independent Trustees voting separately, unanimously approved the continuation
of the investment advisory agreement for another year. In considering the
continuation of the investment advisory agreement, the Trustees considered
various factors that they determined were relevant, including the factors
described below. The Trustees did not identify any single factor as the
controlling factor in determining to approve the continuation of the investment
advisory agreement.


Nature, Extent and Quality of Services
The Trustees considered the nature, extent and quality of the services that
were provided by PIM to the Trust, taking into account the investment objective
and strategy of the Trust and the information related to the Trust provided to
the Trustees at each regularly scheduled meeting. The Trustees reviewed the
terms of the investment advisory agreement. The Trustees also reviewed PIM's
investment approach for the Trust and its research process. The Trustees
considered the resources of PIM and the personnel of PIM who provide investment
management services to the Trust. They also considered PIM's compliance and
legal resources and personnel.

The Trustees also considered that, as administrator, PIM is responsible for the
administration of the Trust's business and other affairs. It was noted that PIM
supervises and monitors the performance of the Trust's service providers and
provides the Trust with personnel (including officers) as are necessary for the



             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    35


Trust's operations. The Trustees considered the fees paid to PIM for the
provision of such services.

Based on these considerations, the Trustees concluded that the nature, extent
and quality of services that were provided by PIM to the Trust were
satisfactory and consistent with the terms of the investment advisory
agreement.


Performance of the Trust
The Trustees considered the performance results of the Trust over various time
periods. They reviewed information comparing the Trust's performance with the
average performance of its peer group of funds as classified by Morningstar,
Inc. (Morningstar), an independent provider of investment company data, and
with the performance of the Trust's benchmark index. The Trustees considered
that the Trust's annualized total return was in the fourth quintile of its
Morningstar category for the one year period ended June 30, 2008 and in the
fifth quintile of its Morningstar category for the three year period ended June
30, 2008. (In all quintile rankings referred to throughout this disclosure,
first quintile is most favorable to the Trust's shareowners. Thus, highest
relative performance would be first quintile and lowest relative expenses would
also be first quintile.) The Trustees noted that the yield (gross of expenses)
to the Trust's common shareowners for the twelve months ended June 30, 2008
trailed the yield of the Trust's benchmark index for the same period. The
Trustees discussed the reasons for the Trust's underperformance with PIM. The
Trustees agreed that they would continue to monitor the performance of the
Trust closely.


Management Fee and Expenses
The Trustees considered information on the fees and expenses of the Trust in
comparison to the management fees and the expense ratios of a peer group of
funds selected on the basis of criteria determined by the independent Trustees
for this purpose using data provided by Strategic Insight Mutual Trust Research
and Consulting, LLC (Strategic Insight), an independent third party.

The Trustees considered that the Trust's management fee for the twelve months
ended June 30, 2008 was in the second quintile relative to the management fees
paid by other funds in its Strategic Insight peer group for the comparable
period. The Trustees also considered that the Trust's expense ratio for the
twelve months ended June 30, 2008 was in the first quintile relative to its
Strategic Insight peer group for the comparable period. It was noted that PIM
did not currently manage any separate accounts with an investment objective and
strategies that were similar to the Trust.

The Trustees concluded that the management fee payable by the Trust to PIM was
reasonable in relation to the nature and quality of the services provided by
PIM. The Trustees also concluded that the Trust's expense ratio was reasonable,
taking into account the nature and quality of services provided by PIM.


36    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


Profitability
The Trustees considered information provided by PIM regarding the profitability
of PIM with respect to the advisory services provided by PIM to the Trust,
including the methodology used by PIM in allocating certain of its costs to the
management of the Trust. The Trustees also considered PIM's profit margin in
connection with the overall operation of the Trust. They further reviewed the
financial results realized by PIM and its affiliates from non-fund businesses.
The Trustees considered PIM's profit margins with respect to the Trust in
comparison to the limited industry data available and noted that the
profitability of any adviser was affected by numerous factors, including its
organizational structure and method for allocating expenses. The Trustees
recognized that PIM should be entitled to earn a reasonable level of profit for
the services provided to the Trust. The Trustees concluded that PIM's
profitability with respect to the management of the Trust was not unreasonable.


Economies of Scale
The Trustees considered the extent to which PIM may realize economies of scale
or other efficiencies in managing and supporting the Trust. Since the Trust is
a closed-end fund and its size is relatively stable at an asset level that was
anticipated when the management fee initially was set, the Trustees concluded
that economies of scale were not a relevant consideration.


Other Benefits
The Trustees also considered the character and amount of fees paid by the
Trust, other than under the investment advisory agreement, for services
provided by PIM and its affiliates. The Trustees further considered the
revenues and profitability of PIM's businesses other than the fund business.
The Trustees concluded that the receipt of these benefits was reasonable in the
context of the overall relationship between PIM and the Trust.


Conclusion
After consideration of the factors described above as well as other factors,
the Trustees, including all of the independent Trustees, concluded that the
investment advisory agreement between PIM and the Trust, including the fees
payable thereunder, was fair and reasonable and voted to approve the proposed
continuation of the investment advisory agreement for the Trust.


             Pioneer Municipal High Income Trust | Annual Report | 4/30/09    37


Trustees, Officers and Service Providers

Investment Adviser
Pioneer Investment Management, Inc.


Custodian
Brown Brothers Harriman & Co.


Independent Registered Public Accounting Firm
Ernst & Young LLP


Legal Counsel
Bingham McCutchen LLP


Transfer Agent
Pioneer Investment Management Shareholder Services, Inc.


Shareowner Services and Sub-Transfer Agent
American Stock Transfer & Trust Company


Preferred Share Auction/Transfer Agent and Registrar
Deutsche Bank Trust Company Americas


Sub-Administrator
Princeton Administrators, LLC


Proxy Voting Policies and Procedures of the Trust are available without charge,
upon request, by calling our toll free number (1-800-225-6292). Information
regarding how the Trust voted proxies relating to portfolio securities during
the most recent 12-month period ended June 30 is publicly available to
shareowners at www.pioneerinvestments.com. This information is also available
on the Securities and Exchange Commission's web site at http://www.sec.gov.


Trustees and Officers

The Board of Trustees provides broad supervision over the Trust's affairs. The
officers of the Trust are responsible for the Trust's operations. The Trustees
and officers are listed below, together with their principal occupations during
the past five years. Trustees who are interested persons of the Trust within
the meaning of the 1940 Act are referred to as Interested Trustees. Trustees
who are not interested persons of the Trust are referred to as Independent
Trustees. Each of the Trustees serves as a Trustee of each of the 67 U.S.
registered investment portfolios for which Pioneer serves as investment adviser
(the "Pioneer Funds"). The address for all Trustees and all officers of the
Trust is 60 State Street, Boston, Massachusetts 02109.


38    Pioneer Municipal High Income Trust | Annual Report | 4/30/09



Interested Trustees


------------------------------------------------------------------------------------------------------------------------------------

                       Position Held     Length of Service                                                Other Directorships
Name and Age           With the Trust    and Term of Office  Principal Occupation During Past Five Years  Held by this Trustee
------------------------------------------------------------------------------------------------------------------------------------
                                                                                              
John F. Cogan, Jr.     Chairman of the   Class I Trustee     Deputy Chairman and a Director of Pioneer    None
(82)*                  Board, Trustee    since 2003.         Global Asset Management S.p.A. ("PGAM");
                       and President     Term expires        Non-Executive Chairman and a Director of
                                         in 2010.            Pioneer Investment Management USA Inc.
                                         Elected by          ("PIM-USA"); Chairman and a Director of
                                         Preferred           Pioneer; Chairman and Director of Pioneer
                                         Shares only.        Institutional Asset Management, Inc. since
                                                             2006); Director of Pioneer Alternative
                                                             Investment Management Limited (Dublin);
                                                             President and a Director of Pioneer
                                                             Alternative Investment Management (Bermuda)
                                                             Limited and affiliated funds; Director of
                                                             PIOGLOBAL Real Estate Investment Fund
                                                             (Russia) (until June 2006); Director of
                                                             Nano-C, Inc. (since 2003); Director of Cole
                                                             Management Inc. (since 2004); Director of
                                                             Fiduciary Counseling, Inc.; President and
                                                             Director of Pioneer Funds Distributor, Inc.
                                                             ("PFD") (until May 2006); President of all
                                                             of the Pioneer Funds; and Of Counsel,
                                                             Wilmer Cutler Pickering Hale and Dorr LLP
------------------------------------------------------------------------------------------------------------------------------------
Daniel K. Kingsbury    Trustee and       Class II Trustee    Director, CEO and President of Pioneer       None
(50)*                  Executive         since 2007.         Investment Management USA Inc. (since
                       Vice President    Term expires        February 2007); Director and President of
                                         in 2011.            Pioneer Investment Management, Inc. and
                                                             Pioneer Institutional Asset Management,
                                                             Inc. (since February 2007); Executive Vice
                                                             President of all of the Pioneer Funds
                                                             (since March 2007); Director of Pioneer
                                                             Global Asset Management S.p.A. (since April
                                                             2007); Head of New Markets Division,
                                                             Pioneer Global Asset Management S.p.A.
                                                             (2000 - 2007)
------------------------------------------------------------------------------------------------------------------------------------


* Mr. Cogan and Mr. Kingsbury are Interested Trustees because they are
  officers or directors of the Trust's investment adviser and certain of its
  affiliates.

               Pioneer Municipal High Income Trust | Annual Report | 4/30/09  39



Independent Trustees


------------------------------------------------------------------------------------------------------------------------------------

                       Position Held     Length of Service                                                Other Directorships
Name and Age           With the Trust    and Term of Office  Principal Occupation During Past Five Years  Held by this Trustee
------------------------------------------------------------------------------------------------------------------------------------
                                                                                              
David R. Bock (65)     Trustee           Class I Trustee     Managing Partner, Federal City Capital       Director of Enterprise
                                         since 2005.         Advisors (boutique merchant bank) (1997 to   Community Investment, Inc.
                                         Term expires        2004 and 2008 - present); and Executive      (privately-held affordable
                                         in 2010.            Vice President and Chief Financial Officer,  housing finance company);
                                                             I-trax, Inc. (publicly traded health care    Director of New York
                                                             services company) (2004 - 2007)              Mortgage Trust (publicly
                                                                                                          traded mortgage REIT); and
                                                                                                          Director of Oxford
                                                                                                          Analytica, Inc.
                                                                                                          (privately-held research
                                                                                                          and consulting company)
------------------------------------------------------------------------------------------------------------------------------------
Mary K. Bush (61)      Trustee           Class III Trustee   President, Bush International, LLC           Director of Marriott
                                         since 2003.         (international financial advisory firm)      International, Inc.;
                                         Term expires                                                     Director of Discover
                                         in 2009.                                                         Financial Services (credit
                                                                                                          card issuer and electronic
                                                                                                          payment services);
                                                                                                          Director of Briggs &
                                                                                                          Stratton Co. (engine
                                                                                                          manufacturer); Director of
                                                                                                          UAL Corporation (airline
                                                                                                          holding company); Director
                                                                                                          of Mantech International
                                                                                                          Corporation (national
                                                                                                          security, defense, and
                                                                                                          intelligence technology
                                                                                                          firm); and Member, Board
                                                                                                          of Governors, Investment
                                                                                                          Company Institute
------------------------------------------------------------------------------------------------------------------------------------


40  Pioneer Municipal High Income Trust | Annual Report | 4/30/09





------------------------------------------------------------------------------------------------------------------------------------

                       Position Held     Length of Service                                                Other Directorships
Name and Age           With the Trust    and Term of Office  Principal Occupation During Past Five Years  Held by this Trustee
------------------------------------------------------------------------------------------------------------------------------------
                                                                                              
Benjamin M. Friedman   Trustee           Class II Trustee    Professor, Harvard University                Trustee, Mellon
(64)                                     since 2008.                                                      Institutional Funds
                                         Term expires                                                     Investment Trust and
                                         in 2011.                                                         Mellon Institutional Funds
                                                                                                          Master Portfolio (oversees
                                                                                                          17 portfolios in fund
                                                                                                          complex)
------------------------------------------------------------------------------------------------------------------------------------
Margaret B.W. Graham   Trustee           Class II Trustee    Founding Director, Vice-President and        None
(61)                                     since 2003.         Corporate Secretary, The Winthrop Group,
                                         Term expires        Inc. (consulting firm); and Desautels
                                         in 2011.            Faculty of Management, McGill University
------------------------------------------------------------------------------------------------------------------------------------
Thomas J. Perna (58)   Trustee           Class III Trustee   Chief Executive Officer, Quadriserv, Inc.    None
                                         since 2006.         (technology products for securities lending
                                         Term expires        industry) (2008 - present); Private
                                         in 2009.            investor (2004 - 2008); and Senior
                                                             Executive Vice President, The Bank of New
                                                             York (financial and securities services)
                                                             (1986 - 2004)
------------------------------------------------------------------------------------------------------------------------------------
Marguerite A. Piret    Trustee           Class III Trustee   President and Chief Executive Officer,       Director of New America
(60)                                     since 2003.         Newbury, Piret & Company, Inc. (investment   High Income Fund, Inc.
                                         Term expires        banking firm)                                (closed-end investment
                                         in 2009. Elected by                                              company)
                                         Preferred Shares
                                         only.
------------------------------------------------------------------------------------------------------------------------------------
Stephen K. West (80)   Trustee           Class I Trustee     Senior Counsel, Sullivan & Cromwell LLP      Director, The Swiss
                                         since 2003.         (law firm)                                   Helvetia Fund, Inc.
                                         Term expires                                                     (closed-end investment
                                         in 2010.                                                         company)
------------------------------------------------------------------------------------------------------------------------------------


               Pioneer Municipal High Income Trust | Annual Report | 4/30/09  41



Trust Officers


------------------------------------------------------------------------------------------------------------------------------------
                       Position Held     Length of Service                                                Other Directorships
Name and Age           With the Trust    and Term of Office  Principal Occupation During Past Five Years  Held by this Officer
------------------------------------------------------------------------------------------------------------------------------------
                                                                                              
Dorothy E. Bourassa    Secretary         Since 2003. Serves  Secretary of PIM-USA; Senior Vice President  None
(61)                                     at the discretion   - Legal of Pioneer; Secretary/Clerk of most
                                         of the Board        of PIM-USA's subsidiaries; and Secretary of
                                                             all of the Pioneer Funds since September
                                                             2003 (Assistant Secretary from November
                                                             2000 to September 2003)
------------------------------------------------------------------------------------------------------------------------------------
Christopher J. Kelley  Assistant         Since 2003. Serves  Associate General Counsel of Pioneer since   None
(44)                   Secretary         at the discretion   January 2008 and Assistant Secretary of all
                                         of the Board        of the Pioneer Funds since September 2003;
                                                             Vice President and Senior Counsel of
                                                             Pioneer from July 2002 to December 2007
------------------------------------------------------------------------------------------------------------------------------------
Mark E. Bradley (49)   Treasurer         Since 2008. Serves  Vice President - Fund Accounting,            None
                                         at the discretion   Administration and Controllership Services
                                         of the Board        of Pioneer; and Treasurer of all of the
                                                             Pioneer Funds since March 2008; Deputy
                                                             Treasurer of Pioneer from March 2004 to
                                                             February 2008; Assistant Treasurer of all
                                                             of the Pioneer Funds from March 2004 to
                                                             February 2008; and Treasurer and Senior
                                                             Vice President, CDC IXIS Asset Management
                                                             Services from 2002 to 2003
------------------------------------------------------------------------------------------------------------------------------------
Luis I. Presutti (44)  Assistant         Since 2003. Serves  Assistant Vice President - Fund Accounting,  None
                       Treasurer         at the discretion   Administration and Controllership Services
                                         of the  Board       of Pioneer; and Assistant Treasurer of all
                                                             of the Pioneer Funds
------------------------------------------------------------------------------------------------------------------------------------
Gary Sullivan (51)     Assistant         Since 2003. Serves  Fund Accounting Manager - Fund Accounting,   None
                       Treasurer         at the discretion   Administration and Controllership Services
                                         of the Board        of Pioneer; and Assistant Treasurer of all
                                                             of the Pioneer Funds
------------------------------------------------------------------------------------------------------------------------------------


42  Pioneer Municipal High Income Trust | Annual Report | 4/30/09





------------------------------------------------------------------------------------------------------------------------------------
                       Position Held     Length of Service                                                Other Directorships
Name and Age           With the Trust    and Term of Office  Principal Occupation During Past Five Years  Held by this Officer
------------------------------------------------------------------------------------------------------------------------------------
                                                                                              
David F. Johnson (29)  Assistant         Since 2009. Serves  Fund Administration Manager - Fund           None
                       Treasurer         at the discretion   Accounting, Administration and
                                         of the Board        Controllership Services since November 2008
                                                             and Assistant Treasurer of all of the
                                                             Pioneer Funds since January 2009; Client
                                                             Service Manager - Institutional Investor
                                                             Services at State Street Bank from March
                                                             2003 to March 2007
------------------------------------------------------------------------------------------------------------------------------------
Teri W. Anderholm (49) Chief Compliance  Since 2007. Serves  Chief Compliance Officer of Pioneer since    None
                       Officer           at the discretion   December 2006 and of all the Pioneer Funds
                                         of the Board        since January 2007; Vice President and
                                                             Compliance Officer, MFS Investment
                                                             Management (August 2005 to December 2006);
                                                             Consultant, Fidelity Investments (February
                                                             2005 to July 2005); Independent Consultant
                                                             (July 1997 to February 2005)
------------------------------------------------------------------------------------------------------------------------------------




               Pioneer Municipal High Income Trust | Annual Report | 4/30/09  43


                           This page for your notes.

44    Pioneer Municipal High Income Trust | Annual Report | 4/30/09


How to Contact Pioneer

We are pleased to offer a variety of convenient ways for you to contact us for
assistance or information.



You can call American Stock Transfer & Trust Company (AST) for:
--------------------------------------------------------------------------------
Account Information                             1-800-710-0935



Or write to AST:
--------------------------------------------------------------------------------
For                                             Write to

General inquiries, lost dividend checks,        American Stock
change of address, lost stock certificates,     Transfer & Trust
stock transfer                                  Operations Center
                                                6201 15th Ave.
                                                Brooklyn, NY 11219

Dividend reinvestment plan (DRIP)               American Stock
                                                Transfer & Trust
                                                Wall Street Station
                                                P.O. Box 922
                                                New York, NY 10269-0560


Visit our web site: www.amstock.com


For additional information, please contact your investment advisor or visit our
web site www.pioneerinvestments.com.

The Trust files a complete statement of investments with the Securities and
Exchange Commission for the first and third quarters for each fiscal year on
Form N-Q. Shareowners may view the filed Form N-Q by visiting the Commission's
web site at http://www.sec.gov. The filed form also may be viewed and copied at
the Commission's Public Reference Room in Washington, DC. Information regarding
the operations of the Public Reference Room may be obtained by calling
1-800-SEC-0330.

The Trust's Chief Executive Officer is required by the New York Stock
Exchange's Listing Standards to file annually with the Exchange a certification
that he is not aware of any violation by the Trust of the Exchange's Corporate
Governance Standards applicable to the Trust. The Trust has filed such
certification.



ITEM 2. CODE OF ETHICS.

(a) Disclose whether, as of the end of the period covered by the report, the
registrant has adopted a code of ethics that applies to the registrant's
principal executive officer, principal financial officer, principal accounting
officer or controller, or persons performing similar functions, regardless of
whether these individuals are employed by the registrant or a third party.  If
the registrant has not adopted such a code of ethics, explain why it has not
done so.

The registrant has adopted, as of the end of the period covered by this report,
a code of ethics that applies to the registrant's principal executive officer,
principal financial officer, principal accounting officer and controller.

(b) For purposes of this Item, the term "code of ethics" means written standards
that are reasonably designed to deter wrongdoing and to promote:

        (1) Honest and ethical conduct, including the ethical handling of actual
        or apparent conflicts of interest between personal and professional
        relationships;

        (2) Full, fair, accurate, timely, and understandable disclosure in
        reports and documents that a registrant files with, or submits to, the
        Commission and in other public communications made by the registrant;

        (3) Compliance with applicable governmental laws, rules, and
        regulations;

        (4) The prompt internal reporting of violations of the code to an
        appropriate person or persons identified in the code; and

        (5) Accountability for adherence to the code.

(c) The registrant must briefly describe the nature of any amendment, during the
period covered by the report, to a provision of its code of ethics that applies
to the registrant's principal executive officer, principal financial officer,
principal accounting officer or controller, or persons performing similar
functions, regardless of whether these individuals are employed by the
registrant or a third party, and that relates to any element of the code of
ethics definition enumerated in paragraph (b) of this Item. The registrant must
file a copy of any such amendment as an exhibit pursuant to Item 10(a), unless
the registrant has elected to satisfy paragraph (f) of this Item by posting its
code of ethics on its website pursuant to paragraph (f)(2) of this Item, or by
undertaking to provide its code of ethics to any person without charge, upon
request, pursuant to paragraph (f)(3) of this Item.

The registrant has made no amendments to the code of ethics during the period
covered by this report.

(d) If the registrant has, during the period covered by the report, granted a
waiver, including an implicit waiver, from a provision of the code of ethics to
the registrant's principal executive officer, principal financial officer,
principal accounting officer or controller, or persons performing similar
functions, regardless of whether these individuals are employed by the
registrant or a third party, that relates to one or more of the items set forth
in paragraph (b) of this Item, the registrant must briefly describe the nature
of the waiver, the name of the person to whom the waiver was granted, and the
date of the waiver.

Not applicable.

(e) If the registrant intends to satisfy the disclosure requirement under
paragraph (c) or (d) of this Item regarding an amendment to, or a waiver from,
a provision of its code of ethics that applies to the registrant's principal
executive officer, principal financial officer, principal accounting officer or
controller, or persons performing similar functions and that relates to any
element of the code of ethics definition enumerated in paragraph (b) of this
Item by posting such information on its Internet website, disclose the
registrant's Internet address and such intention.

Not applicable.

(f) The registrant must:

        (1) File with the Commission, pursuant to Item 10(a), a copy of its code
        of ethics that applies to the registrant's principal executive officer,
        principal financial officer, principal accounting officer or controller,
        or persons performing similar functions, as an exhibit to its annual
        report on this Form N-CSR;

        (2) Post the text of such code of ethics on its Internet website and
        disclose, in its most recent report on this Form N-CSR, its Internet
        address and the fact that it has posted such code of ethics on its
        Internet website; or

        (3) Undertake in its most recent report on this Form N-CSR to provide to
        any person without charge, upon request, a copy of such code of ethics
        and explain the manner in which such request may be made.
	See Item 10(2)

ITEM 3. AUDIT COMMITTEE FINANCIAL EXPERT.

(a) (1)  Disclose that the registrant's board of trustees has determined that
         the registrant either:

    (i)  Has at least one audit committee financial expert serving on its audit
         committee; or

    (ii) Does not have an audit committee financial expert serving on its audit
         committee.

The registrant's Board of Trustees has determined that the registrant has at
least one audit committee financial expert.

    (2) If the registrant provides the disclosure required by paragraph
(a)(1)(i) of this Item, it must disclose the name of the audit committee
financial expert and whether that person is "independent." In order to be
considered "independent" for purposes of this Item, a member of an audit
committee may not, other than in his or her capacity as a member of the audit
committee, the board of trustees, or any other board committee:

    (i)  Accept directly or indirectly any consulting, advisory, or other
         compensatory fee from the issuer; or

    (ii) Be an "interested person" of the investment company as defined in
         Section 2(a)(19) of the Act (15 U.S.C. 80a-2(a)(19)).

Ms. Marguerite A. Piret, an independent trustee, is such an audit committee
financial expert.

    (3) If the registrant provides the disclosure required by paragraph (a)(1)
(ii) of this Item, it must explain why it does not have an audit committee
financial expert.

Not applicable.


ITEM 4. PRINCIPAL ACCOUNTANT FEES AND SERVICES.

(a) Disclose, under the caption AUDIT FEES, the aggregate fees billed for each
of the last two fiscal years for professional services rendered by the principal
accountant for the audit of the registrant's annual financial statements or
services that are normally provided by the accountant in connection with
statutory and regulatory filings or engagements for those fiscal years.

Audit Fees
Fees for audit services provided to the Trust, including fees associated
with the filings to update its Form N-2 and issuance of comfort letters,
totaled approximately $41,300 in 2009 and $38,545 in 2008.

(b) Disclose, under the caption AUDIT-RELATED FEES, the aggregate fees billed in
each of the last two fiscal years for assurance and related services by the
principal accountant that are reasonably related to the performance of the audit
of the registrant's financial statements and are not reported under
paragraph (a) of this Item. Registrants shall describe the nature of the
services comprising the fees disclosed under this category.

Audit-Related Fees
Audit related fees for the Trust's audit related services totaled
approximately $9,652 and $9,285 in 2009 and 2008, respectively.

(c) Disclose, under the caption TAX FEES, the aggregate fees billed in each of
the last two fiscal years for professional services rendered by the principal
accountant for tax compliance, tax advice, and tax planning. Registrants shall
describe the nature of the services comprising the fees disclosed under this
category.

Tax Fees
Fees for tax compliance services, primarily for tax returns,
totaled approximately $8,290 and $7,820 for 2009 and 2008, respectively.

(d) Disclose, under the caption ALL OTHER FEES, the aggregate fees billed in
each of the last two fiscal years for products and services provided by the
principal accountant, other than the services reported in paragraphs (a) through
(c) of this Item. Registrants shall describe the nature of the services
comprising the fees disclosed under this category.

All Other Fees
There were no other fees 2009 and 2008.

(e) (1) Disclose the audit committee's pre-approval policies and procedures
described in paragraph (c)(7) of Rule 2-01 of Regulation S-X.

 PIONEER FUNDS
            APPROVAL OF AUDIT, AUDIT-RELATED, TAX AND OTHER SERVICES
                       PROVIDED BY THE INDEPENDENT AUDITOR

                  SECTION I - POLICY PURPOSE AND APPLICABILITY

The Pioneer Funds recognize the importance of maintaining the independence of
their outside auditors. Maintaining independence is a shared responsibility
involving Pioneer Investment Management, Inc ("PIM"), the audit committee and
the independent auditors.

The Funds recognize that a Fund's independent auditors: 1) possess knowledge of
the Funds, 2) are able to incorporate certain services into the scope of the
audit, thereby avoiding redundant work, cost and disruption of Fund personnel
and processes, and 3) have expertise that has value to the Funds. As a result,
there are situations where it is desirable to use the Fund's independent
auditors for services in addition to the annual audit and where the potential
for conflicts of interests are minimal. Consequently, this policy, which is
intended to comply with Rule 210.2-01(C)(7), sets forth guidelines and
procedures to be followed by the Funds when retaining the independent audit firm
to perform audit, audit-related tax and other services under those
circumstances, while also maintaining independence.

Approval of a service in accordance with this policy for a Fund shall also
constitute approval for any other Fund whose pre-approval is required pursuant
to Rule 210.2-01(c)(7)(ii).

In addition to the procedures set forth in this policy, any non-audit services
that may be provided consistently with Rule 210.2-01 may be approved by the
Audit Committee itself and any pre-approval that may be waived in accordance
with Rule 210.2-01(c)(7)(i)(C) is hereby waived.

Selection of a Fund's independent auditors and their compensation shall be
determined by the Audit Committee and shall not be subject to this policy.



                               SECTION II - POLICY

---------------- -------------------------------- -------------------------------------------------
SERVICE           SERVICE CATEGORY DESCRIPTION      SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES
CATEGORY
---------------- -------------------------------- -------------------------------------------------
                                            
I.  AUDIT        Services that are directly       o Accounting research assistance
SERVICES         related to performing the        o SEC consultation, registration
                 independent audit of the Funds     statements, and reporting
                                                  o Tax accrual related matters
                                                  o Implementation of new accounting
                                                    standards
                                                  o Compliance letters (e.g. rating agency
                                                    letters)
                                                  o Regulatory reviews and assistance
                                                    regarding financial matters
                                                  o Semi-annual reviews (if requested)
                                                  o Comfort letters for closed end
                                                    offerings
---------------- -------------------------------- -------------------------------------------------
II.              Services which are not           o AICPA attest and agreed-upon procedures
AUDIT-RELATED    prohibited under Rule            o Technology control assessments
SERVICES         210.2-01(C)(4) (the "Rule")      o Financial reporting control assessments
                 and are related extensions of    o Enterprise security architecture
                 the audit services support the     assessment
                 audit, or use the
                 knowledge/expertise gained
                 from the audit procedures as a
                 foundation to complete the
                 project.  In most cases, if
                 the Audit-Related Services are
                 not performed by the Audit
                 firm, the scope of the Audit
                 Services would likely
                 increase.  The Services are
                 typically well-defined and
                 governed by accounting
                 professional standards (AICPA,
                 SEC, etc.)
---------------- -------------------------------- -------------------------------------------------

 ------------------------------------- ------------------------------------
                                    
   AUDIT COMMITTEE APPROVAL POLICY               AUDIT COMMITTEE
                                                REPORTING POLICY
 ------------------------------------- ------------------------------------
                                    
 o "One-time" pre-approval             o A summary of all such
   for the audit period for all          services and related fees
   pre-approved specific service         reported at each regularly
   subcategories.  Approval of the       scheduled Audit Committee
   independent auditors as               meeting.
   auditors for a Fund shall
   constitute pre approval for
   these services.
 ------------------------------------- ------------------------------------
 o "One-time" pre-approval             o A summary of all such
   for the fund fiscal year within       services and related fees
   a specified dollar limit              (including comparison to
   for all pre-approved                  specified dollar limits)
   specific service subcategories        reported quarterly.

 o Specific approval is
   needed to exceed the
   pre-approved dollar limit for
   these services (see general
   Audit Committee approval policy
   below for details on obtaining
   specific approvals)

 o Specific approval is
   needed to use the Fund's
   auditors for Audit-Related
   Services not denoted as
   "pre-approved", or
   to add a specific service
   subcategory as "pre-approved"
 ------------------------------------- ------------------------------------




                     SECTION III - POLICY DETAIL, CONTINUED

----------------------- --------------------------- -----------------------------------------------
   SERVICE CATEGORY          SERVICE CATEGORY        SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES
                               DESCRIPTION
----------------------- --------------------------- -----------------------------------------------
                                              
III. TAX SERVICES       Services which are not      o Tax planning and support
                        prohibited by the Rule,     o Tax controversy assistance
                        if an officer of the Fund   o Tax compliance, tax returns, excise
                        determines that using the     tax returns and support
                        Fund's auditor to provide   o Tax opinions
                        these services creates
                        significant synergy in
                        the form of efficiency,
                        minimized disruption, or
                        the ability to maintain a
                        desired level of
                        confidentiality.
----------------------- --------------------------- -----------------------------------------------

------------------------------------- -------------------------
  AUDIT COMMITTEE APPROVAL POLICY         AUDIT COMMITTEE
                                          REPORTING POLICY
------------------------------------- -------------------------
------------------------------------- -------------------------
o "One-time" pre-approval             o A summary of
  for the fund fiscal  year             all such services and
  within a specified dollar limit       related fees
  				        (including comparison
  			                to specified dollar
  			                limits) reported
  			                quarterly.

o Specific approval is
  needed to exceed the
  pre-approved dollar limits for
  these services (see general
  Audit Committee approval policy
  below for details on obtaining
  specific approvals)

o Specific approval is
  needed to use the Fund's
  auditors for tax services not
  denoted as pre-approved, or to add a specific
  service subcategory as
  "pre-approved"
------------------------------------- -------------------------




                     SECTION III - POLICY DETAIL, CONTINUED

----------------------- --------------------------- -----------------------------------------------
   SERVICE CATEGORY          SERVICE CATEGORY        SPECIFIC PRE-APPROVED SERVICE SUBCATEGORIES
                               DESCRIPTION
----------------------- --------------------------- -----------------------------------------------
                                              
IV.  OTHER SERVICES     Services which are not      o Business Risk Management support
                        prohibited by the Rule,     o Other control and regulatory
A. SYNERGISTIC,         if an officer of the Fund     compliance projects
UNIQUE QUALIFICATIONS   determines that using the
                        Fund's auditor to provide
                        these services creates
                        significant synergy in
                        the form of efficiency,
                        minimized disruption,
                        the ability to maintain a
                        desired level of
                        confidentiality, or where
                        the Fund's auditors
                        posses unique or superior
                        qualifications to provide
                        these services, resulting
                        in superior value and
                        results for the Fund.
----------------------- --------------------------- -----------------------------------------------

--------------------------------------- ------------------------
    AUDIT COMMITTEE APPROVAL POLICY         AUDIT COMMITTEE
                                            REPORTING POLICY
------------------------------------- --------------------------
                                   
o "One-time" pre-approval             o A summary of
  for the fund fiscal year within       all such services and
  a specified dollar limit              related fees
  			               (including comparison
  			                to specified dollar
  				        limits) reported
                                        quarterly.
o Specific approval is
  needed to exceed the
  pre-approved dollar limits for
  these services (see general
  Audit Committee approval policy
  below for details on obtaining
  specific approvals)

o Specific approval is
  needed to use the Fund's
  auditors for "Synergistic" or
  "Unique Qualifications" Other
  Services not denoted as
  pre-approved to the left, or to
  add a specific service
  subcategory as "pre-approved"
------------------------------------- --------------------------




                     SECTION III - POLICY DETAIL, CONTINUED

----------------------- ------------------------- -----------------------------------------------
   SERVICE CATEGORY         SERVICE CATEGORY        SPECIFIC PROHIBITED SERVICE SUBCATEGORIES
                              DESCRIPTION
----------------------- ------------------------- -----------------------------------------------
                                            
PROHIBITED  SERVICES    Services which result     1. Bookkeeping or other services
                        in the auditors losing       related to the accounting records or
                        independence status          financial statements of the audit
                        under the Rule.              client*
                                                  2. Financial information systems design
                                                     and implementation*
                                                  3. Appraisal or valuation services,
                                                     fairness* opinions, or
                                                     contribution-in-kind reports
                                                  4. Actuarial services (i.e., setting
                                                     actuarial reserves versus actuarial
                                                     audit work)*
                                                  5. Internal audit outsourcing services*
                                                  6. Management functions or human
                                                     resources
                                                  7. Broker or dealer, investment
                                                     advisor, or investment banking services
                                                  8. Legal services and expert services
                                                     unrelated to the audit
                                                  9. Any other service that the Public
                                                     Company Accounting Oversight Board
                                                     determines, by regulation, is
                                                     impermissible
----------------------- ------------------------- -----------------------------------------------

------------------------------------------- ------------------------------
     AUDIT COMMITTEE APPROVAL POLICY               AUDIT COMMITTEE
                                                  REPORTING POLICY
------------------------------------------- ------------------------------
o These services are not to be              o A summary of all
  performed with the exception of the(*)      services and related
  services that may be permitted              fees reported at each
  if they would not be subject to audit       regularly scheduled
  procedures at the audit client (as          Audit Committee meeting
  defined in rule 2-01(f)(4)) level           will serve as continual
  the firm providing the service.             confirmation that has
  				              not provided any
                                              restricted services.
------------------------------------------- ------------------------------

--------------------------------------------------------------------------------
GENERAL AUDIT COMMITTEE APPROVAL POLICY:
o For all projects, the officers of the Funds and the Fund's auditors will each
  make an assessment to determine that any proposed projects will not impair
  independence.

o Potential services will be classified into the four non-restricted service
  categories and the "Approval of Audit, Audit-Related, Tax and Other
  Services" Policy above will be applied. Any services outside the specific
  pre-approved service subcategories set forth above must be specifically
  approved by the Audit Committee.

o At least quarterly, the Audit Committee shall review a report summarizing the
  services by service category, including fees, provided by the Audit firm as
  set forth in the above policy.

--------------------------------------------------------------------------------


    (2) Disclose the percentage of services described in each of paragraphs (b)
   through (d) of this Item that were approved by the audit committee pursuant
   to paragraph (c)(7)(i)(C) of Rule 2-01 of Regulation S-X.

Beginning with non-audit service contracts entered into on or
after May 6, 2003, the  effective date of the new SEC pre-approval
rules, the Trust's audit committee is required to pre-approve services
to affiliates defined by SEC rules to the extent that the services are
determined to have a direct impact on the operations or financial
reporting of the Trust. For the years ended April 30, 2009 and 2008,
there were no services provided to an affiliate that required the Trust's
audit committee pre-approval.

(f) If greater than 50 percent, disclose the percentage of hours expended on the
principal accountant's engagement to audit the registrant's financial statements
for the most recent fiscal year that were attributed to work performed by
persons other than the principal accountant's full-time, permanent employees.

N/A

(g) Disclose the aggregate non-audit fees billed by the registrant's accountant
for services rendered to the registrant, and rendered to the registrant's
investment adviser (not including any sub-adviser whose role is primarily
portfolio management and is subcontracted with or overseen by another investment
adviser), and any entity controlling, controlled by, or under common control
with the adviser that provides ongoing services to the registrant for each of
the last two fiscal years of the registrant.

The aggregate non-audit fees for the Trust and affiliates,
as previously defined, totaled approximately $8,290 in 2009
and $7,820 in 2008.

(h) Disclose whether the registrant's audit committee of the board of trustees
has considered whether the provision of non-audit services that were rendered to
the registrant's investment adviser (not including any subadviser whose role is
primarily portfolio management and is subcontracted with or overseen by another
investment adviser), and any entity controlling, controlled by, or under common
control with the investment adviser that provides ongoing services to the
registrant that were not pre-approved pursuant to paragraph (c)(7)(ii) of
Rule 2-01 of Regulation S-X is compatible with maintaining the principal
accountant's independence.

The Fund's audit committee of the Board of Trustees has
considered whether the provision of non-audit services that
were rendered to the Affiliates (as defined) that were not pre-
approved pursuant to paragraph (c)(7)(ii) of Rule 2-01 of
Regulation S-X is compatible with maintaining the principal
accountant's independence.

Item 5. Audit Committee of Listed Registrants

(a) If the registrant is a listed issuer as defined in Rule 10A-3
under the Exchange Act (17 CFR 240.10A-3), state whether
or not the registrant has a separately-designated standing
 audit committee established in accordance with Section
3(a)(58)(A) of the Exchange Act (15 U.S.C. 78c(a)(58)(A)).
If the registrant has such a committee, however designated,
identify each committee member. If the entire board of directors
is acting as the registrants audit committee as specified in
Section 3(a)(58)(B) of the Exchange Act (15 U.S.C. 78c(a)(58)(B)),
so state.

The registrant has a separately-designated standing audit
committe eestablished in accordance with Section
3(a)(58)(A) of the Exchange Act (15 U.S.C. 78c(a)(58)(A)).

(b) If applicable, provide the disclosure required by Rule 10A-3(d)
under the Exchange Act (17 CFR 240.10A-3(d)) regarding an exemption
from the listing standards for audit committees.

N/A

Item 6. Schedule of Investments.

File Schedule I Investments in securities of unaffiliated issuers
as of the close of the reporting period as set forth in 210.12-
12 of Regulation S-X [17 CFR 210.12-12], unless the schedule is
included as part of the report to shareholders filed under Item
1 of this Form.

Included in Item 1


ITEM 7. DISCLOSURE OF PROXY VOTING POLICIES AND PROCEDURES FOR
CLOSED-END MANAGEMENT INVESTMENT COMPANIES.

A closed-end management investment company that is filing an annual report on
this Form N-CSR must, unless it invests exclusively in non-voting securities,
describe the policies and procedures that it uses to determine how to vote
proxies relating to portfolio securities, including the procedures that the
company uses when a vote presents a conflict between the interests of its
shareholders, on the one hand, and those of the company's investment adviser;
principal underwriter; or any affiliated person (as defined in Section 2(a)(3)
of the Investment Company Act of 1940 (15 U.S.C. 80a-2(a)(3)) and the rules
thereunder) of the company, its investment adviser, or its principal
underwriter, on the other. Include any policies and procedures of the company's
investment adviser, or any other third party, that the company uses, or that are
used on the company's behalf, to determine how to vote proxies relating to
portfolio securities.

		    Proxy Voting Policies and Procedures of
                       Pioneer Investment Management, Inc.

                            VERSION DATED July, 2004

                                    Overview

   Pioneer Investment Management, Inc. ("Pioneer") is a fiduciary that owes
   each of its client's duties of care and loyalty with respect to all
   services undertaken on the client's behalf, including proxy voting. When
   Pioneer has been delegated proxy-voting authority for a client, the duty of
   care requires Pioneer to monitor corporate events and to vote the proxies.
   To satisfy its duty of loyalty, Pioneer must place its client's interests
   ahead of its own and must cast proxy votes in a manner consistent with the
   best interest of its clients. Pioneer will vote all proxies presented in a
   timely manner.

   The Proxy Voting Policies and Procedures are designed to complement
   Pioneer's investment policies and procedures regarding its general
   responsibility to monitor the performance and/or corporate events of
   companies that are issuers of securities held in accounts managed by
   Pioneer. Pioneer's Proxy Voting Policies summarize Pioneer's position on a
   number of issues solicited by companies held by Pioneer's clients. The
   policies are guidelines that provide a general indication on how Pioneer
   would vote but do not include all potential voting scenarios.

   Pioneer's Proxy Voting Procedures detail monitoring of voting, exception
   votes, and review of conflicts of interest and ensure that case-by-case
   votes are handled within the context of the overall guidelines (i.e. best
   interest of client). The overriding goal is that all proxies for US and
   non-US companies that are received promptly will be voted in accordance
   with Pioneer's policies or specific client instructions. All shares in a
   company held by Pioneer-managed accounts will be voted alike, unless a
   client has given us specific voting instructions on an issue or has not
   delegated authority to us or the Proxy Voting Oversight Group determines
   that the circumstances justify a different approach.

   Pioneer does not delegate the authority to vote proxies relating to its
   clients to any of its affiliates, which include other subsidiaries of
   UniCredito.

   Any questions about these policies and procedures should be directed to the
   Proxy Coordinator.

                                       1


                             Proxy Voting Procedures

   Proxy Voting Service
   Pioneer has engaged an independent proxy voting service to assist in the
   voting of proxies. The proxy voting service works with custodians to ensure
   that all proxy materials are received by the custodians and are processed
   in a timely fashion. To the extent applicable, the proxy voting service
   votes all proxies in accordance with the proxy voting policies established
   by Pioneer. The proxy voting service will refer proxy questions to the
   Proxy Coordinator (described below) for instructions under circumstances
   where: (1) the application of the proxy voting guidelines is unclear; (2) a
   particular proxy question is not covered by the guidelines; or (3) the
   guidelines call for specific instructions on a case-by-case basis. The
   proxy voting service is also requested to call to the Proxy Coordinator's
   attention specific proxy questions that, while governed by a guideline,
   appear to involve unusual or controversial issues. Pioneer reserves the
   right to attend a meeting in person and may do so when it determines that
   the company or the matters to be voted on at the meeting are strategically
   important to its clients.

   Proxy Coordinator
   Pioneer's Director of Investment Operations (the "Proxy Coordinator")
   coordinates the voting, procedures and reporting of proxies on behalf of
   Pioneer's clients. The Proxy Coordinator will deal directly with the proxy
   voting service and, in the case of proxy questions referred by the proxy
   voting service, will solicit voting recommendations and instructions from
   the Director of Portfolio Management US or, to the extent applicable,
   investment sub-advisers. The Proxy Coordinator is responsible for ensuring
   that these questions and referrals are responded to in a timely fashion and
   for transmitting appropriate voting instructions to the proxy voting
   service. The Proxy Coordinator is responsible for verifying with the
   Compliance Department whether Pioneer's voting power is subject to any
   limitations or guidelines issued by the client (or in the case of an
   employee benefit plan, the plan's trustee or other fiduciaries).

   Referral Items
   From time to time, the proxy voting service will refer proxy questions to
   the Proxy Coordinator that are described by Pioneer's policy as to be voted
   on a case-by-case basis, that are not covered by Pioneer's guidelines or
   where Pioneer's guidelines may be unclear with respect to the matter to be
   voted on. Under such certain circumstances, the Proxy Coordinator will seek
   a written voting recommendation from the Director of Portfolio Management
   US. Any such recommendation will include: (i) the manner in which the
   proxies should be voted; (ii) the rationale underlying any such decision;
   and (iii) the disclosure of any contacts or communications made between
   Pioneer and any outside parties concerning the proxy proposal prior to the
   time that the voting instructions are provided. In addition, the Proxy
   Coordinator will ask the Compliance Department to review the question for
   any actual or apparent conflicts of interest as described below under
   "Conflicts of

                                       2


   Interest." The Compliance Department will provide a "Conflicts of Interest
   Report," applying the criteria set forth below under "Conflicts of
   Interest," to the Proxy Coordinator summarizing the results of its review.
   In the absence of a conflict of interest, the Proxy Coordinator will vote
   in accordance with the recommendation of the Director of Portfolio
   Management US.

   If the matter presents a conflict of interest for Pioneer, then the Proxy
   Coordinator will refer the matter to the Proxy Voting Oversight Group for a
   decision. In general, when a conflict of interest is present, Pioneer will
   vote according to the recommendation of the Director of Portfolio
   Management US where such recommendation would go against Pioneer's interest
   or where the conflict is deemed to be immaterial. Pioneer will vote
   according to the recommendation of its proxy voting service when the
   conflict is deemed to be material and the Pioneer's internal vote
   recommendation would favor Pioneer's interest, unless a client specifically
   requests Pioneer to do otherwise. When making the final determination as to
   how to vote a proxy, the Proxy Voting Oversight Group will review the
   report from the Director of Portfolio Management US and the Conflicts of
   Interest Report issued by the Compliance Department.

   Conflicts of Interest
   A conflict of interest occurs when Pioneer's interests interfere, or appear
   to interfere with the interests of Pioneer's clients. Occasionally, Pioneer
   may have a conflict that can affect how its votes proxies. The conflict may
   be actual or perceived and may exist when the matter to be voted on
   concerns:

       o      An affiliate of Pioneer,  such as another company  belonging to
              the UniCredito  Italiano  S.p.A.  banking group (a "UniCredito
              Affiliate");

       o      An issuer of a security for which Pioneer acts as a sponsor,
              advisor, manager, custodian, distributor, underwriter, broker, or
              other similar capacity (including those securities specifically
              declared by PGAM to present a conflict of interest for Pioneer);

       o      An issuer of a security for which UniCredito has informed Pioneer
              that a UniCredito Affiliate acts as a sponsor, advisor, manager,
              custodian, distributor, underwriter, broker, or other similar
              capacity; or

       o      A person with whom Pioneer (or any of its affiliates) has an
              existing, material contract or business relationship that was not
              entered into in the ordinary course of Pioneer's business.

       o      Pioneer will abstain from voting with respect to companies
              directly or indirectly owned by UniCredito Italiano Group, unless
              otherwise directed by a client. In addition, Pioneer will inform
              PGAM Global Compliance and the PGAM Independent Directors before
              exercising such rights.

   Any associate involved in the proxy voting process with knowledge of any
   apparent or actual conflict of interest must disclose such conflict to the
   Proxy Coordinator and the Compliance Department. The Compliance Department
   will review each item referred to Pioneer to determine whether an actual or
   potential conflict of interest with Pioneer exists in connection with the
   proposal(s) to be voted upon. The review will be conducted by comparing the
   apparent parties affected by the proxy proposal being

                                       3


   voted upon against the Compliance Department's internal list of interested
   persons and, for any matches found, evaluating the anticipated magnitude
   and possible probability of any conflict of interest being present. For
   each referral item, the determination regarding the presence or absence of
   any actual or potential conflict of interest will be documented in a
   Conflicts of Interest Report to the Proxy Coordinator.

   Securities Lending
   In conjunction with industry standards Proxies are not available to be
   voted when the shares are out on loan through either Pioneer's lending
   program or a client's managed security lending program. However, Pioneer
   will reserve the right to recall lent securities so that they may be voted
   according to the Pioneer's instructions. If a portfolio manager would like
   to vote a block of previously lent shares, the Proxy Coordinator will work
   with the portfolio manager and Investment Operations to recall the
   security, to the extent possible, to facilitate the vote on the entire
   block of shares.

   Share-Blocking

   "Share-blocking" is a market practice whereby shares are sent to a
   custodian (which may be different than the account custodian) for record
   keeping and voting at the general meeting. The shares are unavailable for
   sale or delivery until the end of the blocking period (typically the day
   after general meeting date).

   Pioneer will vote in those countries with "share-blocking." In the event a
   manager would like to sell a security with "share-blocking", the Proxy
   Coordinator will work with the Portfolio Manager and Investment Operations
   Department to recall the shares (as allowable within the market time-frame
   and practices) and/or communicate with executing brokerage firm. A list of
   countries with "share-blocking" is available from the Investment Operations
   Department upon request.

   Record Keeping
   The Proxy Coordinator shall ensure that Pioneer's proxy voting service:

       o   Retains a copy of the proxy statement received (unless the proxy
           statement is available from the SEC's Electronic Data Gathering,
           Analysis, and Retrieval (EDGAR) system);

       o   Retains a record of the vote cast;

       o   Prepares Form N-PX for filing on behalf of each client that is a
           registered investment company; and

       o   Is able to promptly provide Pioneer with a copy of the voting
           record upon its request.

                                       4


   The Proxy Coordinator shall ensure that for those votes that may require
   additional documentation (i.e. conflicts of interest, exception votes and
   case-by-case votes) the following records are maintained:

       o    A record memorializing the basis for each referral vote cast;

       o    A copy of any document created by Pioneer that was material in
            making the decision on how to vote the subject proxy; and

       o    A copy of any conflict notice, conflict consent or any other
            written communication (including emails or other electronic
            communications) to or from the client (or in the case of an
            employee benefit plan, the plan's trustee or other fiduciaries)
            regarding the subject proxy vote cast by, or the vote
            recommendation of, Pioneer.

       o    Pioneer shall maintain the above records in the client's file for a
            period not less than ten (10) years.

     Disclosure
     Pioneer shall take reasonable measures to inform its clients of the process
     or procedures clients must follow to obtain information regarding how
     Pioneer voted with respect to assets held in their accounts. In addition,
     Pioneer shall describe to clients its proxy voting policies and procedures
     and will furnish a copy of its proxy voting policies and procedures upon
     request. This information may be provided to clients through Pioneer's Form
     ADV (Part II) disclosure, by separate notice to the client, or through
     Pioneer's website.

     Proxy Voting Oversight Group
     The members of the Proxy Voting Oversight Group are Pioneer's: Director of
     Portfolio Management US, Head of Investment Operations, and Director of
     Compliance. Other members of Pioneer will be invited to attend meetings and
     otherwise participate as necessary. The Head of Investment Operations will
     chair the Proxy Voting Oversight Group.

     The Proxy Voting Oversight Group is responsible for developing, evaluating,
     and changing (when necessary) Pioneer's Proxy Voting Policies and
     Procedures. The group meets at least annually to evaluate and review these
     policies and procedures and the services of its third-party proxy voting
     service. In addition, the Proxy Voting Oversight Group will meet as
     necessary to vote on referral items and address other business as
     necessary.

     Amendments
     Pioneer may not amend its Proxy Voting Policies And Procedures without the
     prior approval of the Proxy Voting Oversight Group and its corporate
     parent, Pioneer Global Asset Management S.p.A

                                       5


   Proxy Voting Policies
   Pioneer's sole concern in voting proxies is the economic effect of the
   proposal on the value of portfolio holdings, considering both the short-
   and long-term impact. In many instances, Pioneer believes that supporting
   the company's strategy and voting "for" management's proposals builds
   portfolio value. In other cases, however, proposals set forth by management
   may have a negative effect on that value, while some shareholder proposals
   may hold the best prospects for enhancing it. Pioneer monitors developments
   in the proxy-voting arena and will revise this policy as needed.

   All proxies that are received promptly will be voted in accordance with the
   specific policies listed below. All shares in a company held by
   Pioneer-managed accounts will be voted alike, unless a client has given us
   specific voting instructions on an issue or has not delegated authority to
   us. Proxy voting issues will be reviewed by Pioneer's Proxy Voting
   Oversight Group, which consists of the Director of Portfolio Management US,
   the Director of Investment Operations (the Proxy Coordinator), and the
   Director of Compliance.

   Pioneer has established Proxy Voting Procedures for identifying and
   reviewing conflicts of interest that may arise in the voting of proxies.

   Clients may request, at any time, a report on proxy votes for securities
   held in their portfolios and Pioneer is happy to discuss our proxy votes
   with company management. Pioneer retains a proxy voting service to provide
   research on proxy issues and to process proxy votes.

Administrative
   While administrative items appear infrequently in U.S. issuer proxies, they
   are quite common in non-U.S. proxies.

   We will generally support these and similar management proposals:

       o    Corporate name change.

       o    A change of corporate headquarters.

       o    Stock exchange listing.

       o    Establishment of time and place of annual meeting.

       o    Adjournment or postponement of annual meeting.

       o    Acceptance/approval of financial statements.

       o    Approval of dividend payments, dividend reinvestment plans and other
            dividend-related proposals.

       o    Approval of minutes and other formalities.

                                       6


       o    Authorization of the transferring of reserves and allocation of
            income.

       o    Amendments to authorized signatories.

       o    Approval of accounting method changes or change in fiscal year-end.

       o    Acceptance of labor agreements.

       o    Appointment of internal auditors.

   Pioneer will vote on a case-by-case basis on other routine business;
   however, Pioneer will oppose any routine business proposal if insufficient
   information is presented in advance to allow Pioneer to judge the merit of
   the proposal. Pioneer has also instructed its proxy voting service to
   inform Pioneer of its analysis of any administrative items inconsistent, in
   its view, with supporting the value of Pioneer portfolio holdings so that
   Pioneer may consider and vote on those items on a case-by-case basis.

Auditors
     We normally vote for proposals to:

       o    Ratify the auditors. We will consider a vote against if we are
            concerned about the auditors' independence or their past work for
            the company. Specifically, we will oppose the ratification of
            auditors and withhold votes from audit committee members if
            non-audit fees paid by the company to the auditing firm exceed the
            sum of audit fees plus audit-related fees plus permissible tax
            fees according to the disclosure categories proposed by the
            Securities and Exchange Commission.

       o    Restore shareholder rights to ratify the auditors.

     We will normally oppose proposals that require companies to:

       o    Seek bids from other auditors.

       o    Rotate auditing firms, except where the rotation is statutorily
            required or where rotation would demonstrably strengthen financial
            disclosure.

       o    Indemnify auditors.

       o    Prohibit auditors from engaging in non-audit services for the
            company.

     Board of Directors
     On issues related to the board of directors, Pioneer normally supports
     management. We will, however, consider a vote against management in
     instances where corporate performance has been very poor or where the board
     appears to lack independence.

                                       7


     General Board Issues
     Pioneer will vote for:

       o    Audit, compensation and nominating committees composed of
            independent directors exclusively.

       o    Indemnification for directors for actions taken in good faith in
            accordance with the business judgment rule. We will vote against
            proposals for broader indemnification.

       o    Changes in board size that appear to have a legitimate business
            purpose and are not primarily for anti-takeover reasons.

       o    Election of an honorary director.

     We will vote against:

       o    Minimum stock ownership by directors.

       o    Term limits for directors. Companies benefit from experienced
            directors, and shareholder control is better achieved through
            annual votes.

       o    Requirements for union or special interest representation on the
            board.

       o    Requirements to provide two candidates for each board seat.

     We will vote on a case-by case basis on these issues:

       o    Separate chairman and CEO positions. We will consider voting with
            shareholders on these issues in cases of poor corporate
            performance.

     Elections of Directors
     In uncontested elections of directors we will vote against:

       o    Individual directors with absenteeism above 25% without valid
            reason. We support proposals that require disclosure of director
            attendance.

       o    Insider directors and affiliated outsiders who sit on the audit,
            compensation, stock option or nominating committees. For the
            purposes of our policy, we accept the definition of affiliated
            directors provided by our proxy voting service.

     We will also vote against:

       o    Directors who have failed to act on a takeover offer where the
            majority of shareholders have tendered their shares.

       o    Directors who appear to lack independence or are associated with
            very poor corporate performance.

                                       8


     We will vote on a case-by case basis on these issues:

       o    Re-election of directors who have implemented or renewed a
            dead-hand or modified dead-hand poison pill (a "dead-hand poison
            pill" is a shareholder rights plan that may be altered only by
            incumbent or "dead " directors. These plans prevent a potential
            acquirer from disabling a poison pill by obtaining control of the
            board through a proxy vote).

       o    Contested election of directors.

       o    Prior to phase-in required by SEC, we would consider supporting
            election of a majority of independent directors in cases of poor
            performance.

       o    Mandatory retirement policies.

       o    Directors who have ignored a shareholder proposal that has been
            approved by shareholders for two consecutive years.

     Takeover-Related Measures
     Pioneer is generally opposed to proposals that may discourage takeover
     attempts. We believe that the potential for a takeover helps ensure that
     corporate performance remains high.

     Pioneer will vote for:

       o    Cumulative voting.

       o    Increase ability for shareholders to call special meetings.

       o    Increase ability for shareholders to act by written consent.

       o    Restrictions on the ability to make greenmail payments.

       o    Submitting rights plans to shareholder vote.

       o    Rescinding shareholder rights plans ("poison pills").

       o    Opting out of the following state takeover statutes:

     o Control share acquisition statutes, which deny large holders voting
       rights on holdings over a specified threshold.

     o Control share cash-out provisions, which require large holders to
       acquire shares from other holders.

     o Freeze-out provisions, which impose a waiting period on large
       holders before they can attempt to gain control.

     o Stakeholder laws, which permit directors to consider interests of
       non-shareholder constituencies.

                                       9


     o Disgorgement provisions, which require acquirers to disgorge profits
       on purchases made before gaining control.

     o Fair price provisions.

     o Authorization of shareholder rights plans.

     o Labor protection provisions.

     o Mandatory classified boards.

     We will vote on a case-by-case basis on the following issues:

       o    Fair price provisions. We will vote against provisions requiring
            supermajority votes to approve takeovers. We will also consider
            voting against proposals that require a supermajority vote to
            repeal or amend the provision. Finally, we will consider the
            mechanism used to determine the fair price; we are generally
            opposed to complicated formulas or requirements to pay a premium.

       o    Opting out of state takeover statutes regarding fair price
            provisions. We will use the criteria used for fair price
            provisions in general to determine our vote on this issue.

       o    Proposals that allow shareholders to nominate directors.

     We will vote against:

       o    Classified boards, except in the case of closed-end mutual funds.

       o    Limiting shareholder ability to remove or appoint directors. We
            will support proposals to restore shareholder authority in this
            area. We will review on a case-by-case basis proposals that
            authorize the board to make interim appointments.

       o    Classes of shares with unequal voting rights.

       o    Supermajority vote requirements.

       o    Severance packages ("golden" and "tin" parachutes). We will support
            proposals to put these packages to shareholder vote.

       o    Reimbursement of dissident proxy solicitation expenses. While we
            ordinarily support measures that encourage takeover bids, we
            believe that management should have full control over corporate
            funds.

       o    Extension of advance notice requirements for shareholder proposals.

       o    Granting board authority normally retained by shareholders (e.g.,
            amend charter, set board size).

       o    Shareholder rights plans ("poison pills"). These plans generally
            allow shareholders to buy additional shares at a below-market
            price in the event of a change in control and may deter some bids.

                                       10


     Capital Structure
     Managements need considerable flexibility in determining the company's
     financial structure, and Pioneer normally supports managements' proposals
     in this area. We will, however, reject proposals that impose high barriers
     to potential takeovers.

     Pioneer will vote for:

       o    Changes in par value.

       o    Reverse splits, if accompanied by a reduction in number of shares.

       o    Share repurchase programs, if all shareholders may participate on
            equal terms.

       o    Bond issuance.

       o    Increases in "ordinary" preferred stock.

       o    Proposals to have blank-check common stock placements (other than
            shares issued in the normal course of business) submitted for
            shareholder approval.

       o    Cancellation of company treasury shares.

     We will vote on a case-by-case basis on the following issues:

       o    Reverse splits not accompanied by a reduction in number of shares,
            considering the risk of delisting.

       o    Increase in authorized common stock. We will make a determination
            considering, among other factors:

     o Number of shares currently available for issuance;

     o Size of requested increase (we would normally approve increases of up to
       100% of current authorization);

     o Proposed use of the additional shares; and

     o Potential consequences of a failure to increase the number of shares
       outstanding (e.g., delisting or bankruptcy).

       o    Blank-check preferred. We will normally oppose issuance of a new
            class of blank-check preferred, but may approve an increase in a
            class already outstanding if the company has demonstrated that it
            uses this flexibility appropriately.

       o    Proposals to submit private placements to shareholder vote.

       o    Other financing plans.

     We will vote against preemptive rights that we believe limit a company's
financing flexibility.

                                      11


     Compensation
     Pioneer supports compensation plans that link pay to shareholder returns
     and believes that management has the best understanding of the level of
     compensation needed to attract and retain qualified people. At the same
     time, stock-related compensation plans have a significant economic impact
     and a direct effect on the balance sheet. Therefore, while we do not want
     to micromanage a company's compensation programs, we will place limits on
     the potential dilution these plans may impose.

     Pioneer will vote for:

       o    401(k) benefit plans.

       o    Employee stock ownership plans (ESOPs), as long as shares
            allocated to ESOPs are less than 5% of outstanding shares. Larger
            blocks of stock in ESOPs can serve as a takeover defense. We will
            support proposals to submit ESOPs to shareholder vote.

       o    Various issues related to the Omnibus Budget and Reconciliation Act
            of 1993 (OBRA), including:

     o Amendments to performance plans to conform with OBRA;

     o Caps on annual grants or amendments of administrative features;

     o Adding performance goals; and

     o Cash or cash-and-stock bonus plans.

       o    Establish a process to link pay, including stock-option grants, to
            performance, leaving specifics of implementation to the company.

       o    Require that option repricings be submitted to shareholders.

       o    Require the expensing of stock-option awards.

       o    Require reporting of executive retirement benefits (deferred
            compensation, split-dollar life insurance, SERPs, and pension
            benefits).

       o    Employee stock purchase plans where the purchase price is equal to
            at least 85% of the market price, where the offering period is no
            greater than 27 months and where potential dilution (as defined
            below) is no greater than 10%.

                                       12


     We will vote on a case-by-case basis on the following issues:

       o    Executive and director stock-related compensation plans. We will
            consider the following factors when reviewing these plans:

       o    The program must be of a reasonable size. We will approve plans
            where the combined employee and director plans together would
            generate less than 15% dilution. We will reject plans with 15% or
            more potential dilution.

            Dilution = (A + B + C) / (A + B + C + D), where

            A = Shares reserved for plan/amendment,

            B = Shares available under continuing plans,

            C = Shares granted but unexercised and

            D = Shares outstanding.

       o    The plan must not:

            o   Explicitly permit unlimited option repricing authority or that
                have repriced in the past without shareholder approval.

            o   Be a self-replenishing "evergreen" plan, plans that grant
                discount options and tax offset payments.

     o We are generally in favor of proposals that increase participation beyond
       executives.

     o We generally support proposals asking companies to adopt rigorous
       vesting provisions for stock option plans such as those that vest
       incrementally over, at least, a three- or four-year period with a pro
       rata portion of the shares becoming exercisable on an annual basis
       following grant date.

     o We generally support proposals asking companies to disclose their
       window period policies for stock transactions. Window period policies
       ensure that employees do not exercise options based on insider
       information contemporaneous with quarterly earnings releases and other
       material corporate announcements.

     o We generally support proposals asking companies to adopt stock holding
       periods for their executives.

       o    All other employee stock purchase plans.

       o    All other compensation-related proposals, including deferred
            compensation plans, employment agreements, loan guarantee programs
            and retirement plans.

       o    All other proposals regarding stock compensation plans, including
            extending the life of a plan, changing vesting restrictions,
            repricing options, lengthening exercise periods or accelerating
            distribution of awards and pyramiding and cashless exercise
            programs.

                                       13


     We will vote against:

       o    Pensions for non-employee directors. We believe these retirement
            plans reduce director objectivity.

       o    Elimination of stock option plans.

     We will vote on a case-by case basis on these issues:

       o    Limits on executive and director pay.

       o    Stock in lieu of cash compensation for directors.

     Corporate Governance
     Pioneer will vote for:

       o    Confidential Voting.

       o    Equal access provisions, which allow shareholders to contribute
            their opinion to proxy materials.

       o    Proposals requiring directors to disclose their ownership of shares
            in the company.

     We will vote on a case-by-case basis on the following issues:

       o    Change in the state of incorporation. We will support
            reincorporations supported by valid business reasons. We will
            oppose those that appear to be solely for the purpose of
            strengthening takeover defenses.

       o    Bundled proposals. We will evaluate the overall impact of the
            proposal.

       o    Adopting or amending the charter, bylaws or articles of association.

       o    Shareholder appraisal rights, which allow shareholders to demand
            judicial review of an acquisition price.

     We will vote against:

       o    Shareholder advisory committees. While management should solicit
            shareholder input, we prefer to leave the method of doing so to
            management's discretion.

       o    Limitations on stock ownership or voting rights.

       o    Reduction in share ownership disclosure guidelines.

                                       14


     Mergers and Restructurings
     Pioneer will vote on the following and similar issues on a case-by-case
     basis:

       o    Mergers and acquisitions.

       o    Corporate restructurings, including spin-offs, liquidations, asset
            sales, joint ventures, conversions to holding company and
            conversions to self-managed REIT structure.

       o    Debt restructurings.

       o    Conversion of securities.

       o    Issuance of shares to facilitate a merger.

       o    Private placements, warrants, convertible debentures.

       o    Proposals requiring management to inform shareholders of merger
            opportunities.

     We will normally vote against shareholder proposals requiring that the
     company be put up for sale.

     Mutual Funds
     Many of our portfolios may invest in shares of closed-end mutual funds or
     exchange-traded funds. The non-corporate structure of these investments
     raises several unique proxy voting issues.

     Pioneer will vote for:

       o    Establishment of new classes or series of shares.

       o    Establishment of a master-feeder structure.

     Pioneer will vote on a case-by-case on:

       o    Changes in investment policy. We will normally support changes
            that do not affect the investment objective or overall risk level
            of the fund. We will examine more fundamental changes on a
            case-by-case basis.

       o    Approval of new or amended advisory contracts.

       o    Changes from closed-end to open-end format.

       o    Authorization for, or increase in, preferred shares.

       o    Disposition of assets, termination, liquidation, or mergers.

       o    Classified boards of closed-end mutual funds, but will typically
            support such proposals.

                                       15


     Social Issues
     Pioneer will abstain on stockholder proposals calling for greater
     disclosure of corporate activities with regard to social issues. "Social
     Issues" may generally be described as shareholder proposals for a company
     to:

       o    Conduct studies regarding certain issues of public concern and
            interest;

       o    Study the feasibility of the company taking certain actions with
            regard to such issues; or

       o    Take specific action, including ceasing certain behavior and
            adopting company standards and principles, in relation to issues
            of public concern and interest.

     We believe these issues are important and should receive management
     attention.

     Pioneer will vote against proposals calling for substantial changes in the
     company's business or activities. We will also normally vote against
     proposals with regard to contributions, believing that management should
     control the routine disbursement of funds.

                                       16




Item 8. Portfolio Managers of Closed-End Management Investment
        Companies.

(a) If the registrant is a closed-end management investment company that
is filing an annual report on this Form N-CSR,provide the following
information:
(1) State the name, title, and length of service of the person or persons
employed by or associated with the registrant or an investment adviser
of the registrant who are primarily responsible for the day-to-day management
of the registrants portfolio (Portfolio Manager). Also state each Portfolio
Managers business experience during the past 5 years.



                             MUNI HIGH INCOME TRUST


PORTFOLIO MANAGEMENT

Additional Information About the Portfolio Managers

Other Accounts Managed by the Portfolio Managers. The table below indicates, for
each portfolio manager of the fund, information about the accounts other than
the fund over which the portfolio manager has day-to-day investment
responsibility. All information on the number of accounts and total assets in
the table is as of April 30, 2008. For purposes of the table, "Other Pooled
Investment Vehicles" may include investment partnerships, undertakings for
collective investments in transferable securities ("UCITS") and other non-U.S.
investment funds and group trusts, and "Other Accounts" may include separate
accounts for institutions or individuals, insurance company general or separate
accounts, pension funds and other similar institutional accounts but generally
do not include the portfolio manager's personal investment accounts or those
which the manager may be deemed to own beneficially under the code of ethics.
Certain funds and other accounts managed by the portfolio manager may have
substantially similar investment strategies



                                                                                           

--------------------- -------------------- ----------------- ------------------- ------------------ -------------------
Name of Portfolio     Type of Account      Number of         Total Assets        Number of          Assets Managed
Manager                                    Accounts Managed  Managed             Accounts Managed   for which
                                                                                 for which          Advisory Fee is
                                                                                 Advisory Fee is    Performance-Based
                                                                                 Performance-Based
--------------------- -------------------- ----------------- ------------------- ------------------ -------------------
--------------------- -------------------- ----------------- ------------------- ------------------ -------------------
David Eurkus          Other Registered     5                 $1,338,897,000      N/A                N/A
                      Investment
                      Companies
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      Other Pooled         0                 N/A                 N/A                N/A
                      Investment Vehicles
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      Other Accounts       1                 $10,510,000         N/A                N/A
--------------------- -------------------- ----------------- ------------------- ------------------ -------------------



--------------------- -------------------- ----------------- ------------------- ------------------ -------------------
Name of Portfolio     Type of Account      Number of         Total Assets        Number of          Assets Managed
Manager                                    Accounts Managed  Managed             Accounts Managed   for which
                                                                                 for which          Advisory Fee is
                                                                                 Advisory Fee is    Performance-Based
                                                                                 Performance-Based
--------------------- -------------------- ----------------- ------------------- ------------------ -------------------
--------------------- -------------------- ----------------- ------------------- ------------------ -------------------
Timothy Pynchon       Other Registered     5                 $1,338,897,000      N/A                N/A
                      Investment
                      Companies
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      Other Pooled         0                 N/A                 N/A                N/A
                      Investment Vehicles
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      -------------------- ----------------- ------------------- ------------------ -------------------
                      Other Accounts       0                 N/A                 N/A                N/A
--------------------- -------------------- ----------------- ------------------- ------------------ -------------------




Potential Conflicts of Interest. When a portfolio manager is responsible for the
management of more than one account, the potential arises for the portfolio
manager to favor one account over another. The principal types of potential
conflicts of interest that may arise are discussed below. For the reasons
outlined below, Pioneer does not believe that any material conflicts are likely
to arise out of a portfolio manager's responsibility for the management of the
fund as well as one or more other accounts. Although Pioneer has adopted
procedures that it believes are reasonably designed to detect and prevent
violations of the federal securities laws and to mitigate the potential for
conflicts of interest to affect its portfolio management decisions, there can be
no assurance that all conflicts will be identified or that all procedures will
be effective in mitigating the potential for such risks. Generally, the risks of
such conflicts of interest are increased to the extent that a portfolio manager
has a financial incentive to favor one account over another. Pioneer has
structured its compensation arrangements in a manner that is intended to limit
such potential for conflicts of interest. The fund's investment subadviser also
has adopted certain compliance procedures which are designed to address these
types of conflicts. However, there is no guarantee that such procedures will
detect each situation in which a conflict might arise. See "Compensation of
Portfolio Managers" below.

     o    A portfolio manager could favor one account over another in allocating
          new investment opportunities that have limited supply, such as initial
          public offerings and private  placements.  If, for example, an initial
          public offering that was expected to appreciate in value significantly
          shortly  after the offering was  allocated to a single  account,  that
          account may be expected to have  better  investment  performance  than
          other  accounts  that did not  receive an  allocation  of the  initial
          public  offering.  Generally,  investments  for which there is limited
          availability  are  allocated  based upon a range of factors  including
          available  cash  and   consistency   with  the  accounts'   investment
          objectives  and  policies.  This  allocation  methodology  necessarily
          involves some  subjective  elements but is intended over time to treat
          each client in an equitable and fair manner. Generally, the investment
          opportunity is allocated  among  participating  accounts on a pro rata
          basis.  Although  Pioneer  believes that its practices are  reasonably
          designed to treat each client in an equitable  and fair manner,  there
          may be instances where a fund may not participate,  or may participate
          to a  lesser  degree  than  other  clients,  in the  allocation  of an
          investment opportunity.

     o    A portfolio  manager could favor one account over another in the order
          in which trades for the accounts  are placed.  If a portfolio  manager
          determines  to  purchase  a security  for more than one  account in an
          aggregate  amount that may influence the market price of the security,
          accounts that  purchased or sold the security first may receive a more
          favorable price than accounts that made subsequent  transactions.  The
          less liquid the market for the security or the greater the  percentage
          that the proposed  aggregate  purchases or sales  represent of average
          daily trading volume, the greater the potential for accounts that make
          subsequent  purchases or sales to receive a less favorable price. When
          a portfolio manager intends to trade the same security on the same day
          for more than one account,  the trades  typically are "bunched," which
          means that the trades for the  individual  accounts are aggregated and
          each account receives the same price. There are some types of accounts
          as to which bunching may not be possible for contractual reasons (such
          as  directed  brokerage  arrangements).  Circumstances  may also arise
          where the trader  believes  that bunching the orders may not result in
          the best possible  price.  Where those accounts or  circumstances  are
          involved,  Pioneer will place the order in a manner intended to result
          in as favorable a price as possible for such client.

     o    A portfolio manager could favor an account if the portfolio  manager's
          compensation  is tied to the  performance of that account to a greater
          degree than other accounts managed by the portfolio  manager.  If, for
          example,  the  portfolio  manager  receives  a bonus  based  upon  the
          performance of certain  accounts  relative to a benchmark  while other
          accounts are disregarded for this purpose,  the portfolio manager will
          have a financial incentive to seek to have the accounts that determine
          the portfolio manager's bonus achieve the best possible performance to
          the  possible  detriment  of other  accounts.  Similarly,  if  Pioneer
          receives a  performance-based  advisory fee, the portfolio manager may
          favor that  account,  whether or not the  performance  of that account
          directly determines the portfolio manager's compensation.

     o    A portfolio  manager could favor an account if the  portfolio  manager
          has a beneficial  interest in the account, in order to benefit a large
          client or to compensate a client that had poor  returns.  For example,
          if the portfolio manager held an interest in an investment partnership
          that was one of the accounts  managed by the  portfolio  manager,  the
          portfolio  manager  would  have an  economic  incentive  to favor  the
          account in which the portfolio manager held an interest.

     o    If the different accounts have materially and potentially  conflicting
          investment  objectives  or  strategies,  a conflict of interest  could
          arise. For example,  if a portfolio  manager  purchases a security for
          one account and sells the same  security  for  another  account,  such
          trading  pattern may  disadvantage  either the account that is long or
          short. In making portfolio manager assignments, Pioneer seeks to avoid
          such potentially  conflicting  situations.  However, where a portfolio
          manager  is  responsible   for  accounts  with  differing   investment
          objectives  and policies,  it is possible  that the portfolio  manager
          will conclude that it is in the best interest of one account to sell a
          portfolio security while another account continues to hold or increase
          the holding in such security.

Compensation of Portfolio Managers. Pioneer has adopted a system of compensation
for portfolio managers that seeks to align the financial interests of the
portfolio managers with those of shareholders of the accounts (including Pioneer
funds) the portfolio managers manage, as well as with the financial performance
of Pioneer. The compensation program for all Pioneer portfolio managers includes
a base salary (determined by the rank and tenure of the employee) and an annual
bonus program, as well as customary benefits that are offered generally to all
full-time employees. Base compensation is fixed and normally reevaluated on an
annual basis. Pioneer seeks to set base compensation at market rates, taking
into account the experience and responsibilities of the portfolio manager. The
bonus plan is intended to provide a competitive level of annual bonus
compensation that is tied to the portfolio manager achieving superior investment
performance and align the interests of the investment professional with those of
shareholders, as well as with the financial performance of Pioneer. Any bonus
under the plan is completely discretionary, with a maximum annual bonus that may
be in excess of base salary. The annual bonus is based upon a combination of the
following factors:

     o    Quantitative  Investment  Performance.   The  quantitative  investment
          performance  calculation is based on pre-tax investment performance of
          all of the accounts  managed by the portfolio  manager (which includes
          the fund and any other accounts managed by the portfolio manager) over
          a  one-year   period  (20%   weighting)  and  four-year   period  (80%
          weighting),  measured for periods ending on December 31. The accounts,
          which  include the fund,  are ranked  against a group of mutual  funds
          with similar  investment  objectives and investment  focus (60%) and a
          broad-based  securities  market index measuring the performance of the
          same type of securities in which the accounts invest (40%),  which, in
          the case of the fund, is the Barclay's  Capital  Municipal  Bond Index
          and the  Barclay's  Capital  High  Yield  Municipal  Bond Index . As a
          result of these  two  benchmarks,  the  performance  of the  portfolio
          manager for  compensation  purposes is measured  against the  criteria
          that are relevant to the portfolio manager's competitive universe.

     o    Qualitative  Performance.  The qualitative  performance component with
          respect  to all of  the  accounts  managed  by the  portfolio  manager
          includes  objectives,  such as effectiveness in the areas of teamwork,
          leadership,   communications   and   marketing,   that  are   mutually
          established and evaluated by each portfolio manager and management.

     o    Pioneer  Results  and  Business  Line  Results.   Pioneer's  financial
          performance,  as well as the investment  performance of its investment
          management  group,  affect a  portfolio  manager's  actual  bonus by a
          leverage factor of plus or minus (+/-) a predetermined percentage.

The quantitative and qualitative performance components comprise 80% and 20%,
respectively, of the overall bonus calculation (on a pre-adjustment basis). A
portion of the annual bonus is deferred for a specified period and may be
invested in one or more Pioneer funds.

Certain portfolio managers may participate in other programs designed to reward
and retain key contributors. Senior executives or other key employees may be
granted performance units based on the stock price performance of UniCredit and
the financial performance of Pioneer Global Asset Management S.p.A., which are
affiliates of Pioneer. Portfolio managers also may participate in a deferred
compensation program, whereby deferred amounts are invested in one or more
Pioneer funds.



Share Ownership by Portfolio Managers. The following table indicates as of April
30, 2009 the value, within the indicated range, of shares beneficially owned by
the portfolio managers of the fund.

                                                      

--------------------------------------- -----------------------------------------------------------------
Name of Portfolio Manager               Beneficial Ownership of the Fund*
--------------------------------------- -----------------------------------------------------------------
--------------------------------------- -----------------------------------------------------------------
David Eurkus                            A
--------------------------------------- -----------------------------------------------------------------
--------------------------------------- -----------------------------------------------------------------
Timothy Pynchon                         B
--------------------------------------- -----------------------------------------------------------------



*Key to Dollar Ranges

A. None
B. $1 - $10,000
C. $10,001 - $50,000
D. $50,001 - $100,000
E. $100,001 - $500,000
F. $500,001 - $1,000,000
G. Over $1,000,000












                                                                                    

--------------------------------------------------------------------------------------------------------------------------
Interested Trustees:
--------------------------------------------------------------------------------------------------------------------------
------------------- ------------------ ------------------ ---------------------------------- -----------------------------
John F. Cogan,      Chairman of the    Class I Trustee    Deputy Chairman and a Director     None
Jr. (81)*           Board, Trustee     since 2003. Term   of Pioneer Global Asset
                    and President      expires in 2010.   Management S.p.A. ("PGAM");
                                       Elected by         Non-Executive Chairman and a
                                       Preferred Shares   Director of Pioneer Investment
                                       only.              Management USA Inc. ("PIM-USA");
                                                          Chairman and a Director of
                                                          Pioneer; Chairman and Director
                                                          of Pioneer Institutional Asset
                         Management, Inc. (since 2006);
                                                          Director of Pioneer Alternative
                                                          Investment Management Limited
                                                          (Dublin); President and a
                                                          Director of Pioneer Alternative
                                                          Investment Management (Bermuda)
                                                          Limited and affiliated funds;
                                                          Director of PIOGLOBAL Real
                                                          Estate Investment Fund (Russia)
                                                          (until June 2006); Director of
                                                          Nano-C, Inc. (since 2003);
                                                          Director of Cole Management Inc.
                                                          (since 2004); Director of
                                                          Fiduciary Counseling, Inc.;
                                                          President and Director of
                                                          Pioneer Funds Distributor, Inc.
                                                          ("PFD") (until May 2006);
                                                          President of all of the Pioneer
                                                          Funds; and Of Counsel, Wilmer
                                                          Cutler Pickering Hale and Dorr
                                                          LLP
------------------- ------------------ ------------------ ---------------------------------- -----------------------------
------------------- ------------------ ------------------ ---------------------------------- -----------------------------
Daniel K.           Trustee and        Class II Trustee   Director, CEO and President of     None
Kingsbury (49)*     Executive Vice     since 2007. Term   Pioneer Investment Management
                    President          expires in 2011.   USA Inc., Pioneer Investment
                                                          Management, Inc. and Pioneer
                                                          Institutional Asset Management,
                                                          Inc. (since March 2007);
                                                          Executive Vice President of all
                                                          of the Pioneer Funds (since
                                                          March 2007); Director of Pioneer
                                                          Global Asset Management S.p.A.
                                                          (since March 2007); Head of New
                                                          Markets Division, Pioneer Global
                                                          Asset Management S.p.A.
                                                          (2000-2007)
------------------- ------------------ ------------------ ---------------------------------- -----------------------------
--------------------------------------------------------------------------------------------------------------------------
Independent Trustees:
--------------------------------------------------------------------------------------------------------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
David R. Bock (63)       Trustee       Class I Trustee    Executive Vice President and       Director of The Enterprise
                                       since 2005. Term   Chief Financial Officer, I-trax,   Social Investment Company
                                       expires in 2010.   Inc. (publicly traded health       (privately-held affordable
                                                          care services company)
                                                          (2004 - housing
                                                          finance company);
                                                          present); Partner,
                                                          Federal City and
                                                          Director of New York
                                                          Capital Advisors
                                                          (boutique Mortgage
                                                          Trust (publicly
                                                          merchant bank)(1997 to
                                                          2004); traded mortgage
                                                          REIT) and Executive
                                                          Vice President and
                                                          Chief Financial Officer,
                                                          Pedestal Inc. (internet-based
                                                          mortgage trading company)
                                                          (2000-2002)

------------------------ ------------- ------------------ ---------------------------------- -----------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
Mary K. Bush (59)        Trustee       Class III          President, Bush International,     Director of Brady
                                       Trustee since      LLC (international financial       Corporation (industrial
                                       2003. Term         advisory firm)                     identification and
                                       expires in 2009.                                      specialty coated material
                                                                                             products manufacturer);
                                                                                             Director of Briggs &
                                                                                             Stratton Co. (engine
                                                                                             manufacturer); Director of
                                                                                             UAL Corporation (airline
                                                                                             holding company); Director
                                                                                             of Mantech International
                                                                                             Corporation (national
                                                                                             security, defense, and
                                                                                             intelligence technology
                                                                                             firm): and Member, Board of
                                                                                             Governors, Investment
                                                                                             Company Institute
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
Benjamin M. Friedman     Trustee       Class II Trustee   Professor,                         Trustee, Mellon
(64)                                   since 2008. Term   Harvard                            Institutional Funds
                                       expires in 2011.   University                         Investment Trust and Mellon
                                                                                             Institutional Funds Master
                                                                                             Portfolio (oversees 17
                                                                                             portfolios in fund complex)
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
Margaret B.W. Graham     Trustee       Class II Trustee   Founding Director,                 None
(60)                                   since 2003. Term   Vice-President and Corporate
                                       expires in 2011.   Secretary, The Winthrop Group,
                                                          Inc. (consulting firm); and
                                                          Desautels Faculty of Management,
                                                          McGill
                                                          University
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
Thomas J. Perna (57)     Trustee       Class III          Private investor (2004 -           Director of Quadriserv Inc.
                                       Trustee since      present); and Senior Executive     (technology products for
                                       2006. Term         Vice President, The Bank of New    securities lending
                                       expires in 2009.   York (financial and securities     industry)
                                                          services) (1986 -
2004)

------------------------ ------------- ------------------ ---------------------------------- -----------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
Marguerite A. Piret      Trustee       Class III          President and Chief Executive      Director of New America
(59)                                   Trustee since      Officer, Newbury, Piret &          High Income Fund, Inc.
                                       2003. Term         Company, Inc. (investment          (closed-end investment
                                       expires in 2009.   banking firm)                      company)
                                       Elected by
                                       Preferred Shares
                                       only.


------------------------ ------------- ------------------ ---------------------------------- -----------------------------
------------------------ ------------- ------------------ ---------------------------------- -----------------------------
Stephen K. West (79)     Trustee       Class I Trustee    Senior Counsel, Sullivan &         Director, The Swiss
                                       since 2003. Term   Cromwell (law firm)                Helvetia Fund, Inc.
                                       expires in 2010.                                      (closed-end investment
                                                                                             company)

------------------------ ------------- ------------------ ---------------------------------- -----------------------------




Item 9. Purchases of Equity Securities by Closed-End Management
Investment Company and Affiliated Purchasers.

(a) If the registrant is a closed-end management investment company,
in the following tabular format, provide the information specified in
paragraph (b) of this Item with respect to any purchase made by or on
behalf of the registrant or any affiliated purchaser, as defined in
Rule 10b-18(a)(3) under the Exchange Act (17 CFR 240.10b-18(a)(3)), of
shares or other units of any class of the registrants equity securities
that is registered by the registrant pursuant to Section 12 of the
Exchange Act (15 U.S.C. 781). Instruction to paragraph (a). Disclose
all purchases covered by this Item, including purchases that do not
satisfy the conditions of the safe harbor of Rule 10b-18 under the
Exchange Act (17 CFR 240.10b-18), made in the period covered by the
report. Provide disclosures covering repurchases made on a monthly basis.
For example, if the reporting period began on January 16 and ended on
July 15, the chart would show repurchases for the months from January 16
through February 15, February 16 through March 15, March 16 through
April 15, April 16 through May 15, May 16 through June 15, and June 16
through July 15.

During the period covered by this report, there were no purchases
made by or on behalf of the registrant or any affiliated purchaser
as defined in Rule 10b-18(a)(3) under the Securities Exchange Act
of 1934 (the Exchange Act), of shares of the registrants equity
securities that are registered by the registrant pursuant to
Section 12 of the Exchange Act.


Item 10. Submission of Matters to a Vote of Security Holders.

Describe any material changes to the procedures by which shareholders
may recommend nominees to the registrants board of directors, where
those changes were implemented after the registrant last provided
disclosure in response to the requirements of Item 7(d)(2)(ii)(G)
of Schedule 14A (17 CFR 240.14a-101), or this Item.


There have been no material changes to the procedures by which the
shareholders may recommend nominees to the registrants board of
directors since the registrant last provided disclosure in response
to the requirements of Item 7(d)(2)(ii)(G) of Schedule 14(A) in
its definitive proxy statement, or this Item.


ITEM 11. CONTROLS AND PROCEDURES.

(a) Disclose the conclusions of the registrant's principal executive officer or
officers and principal financial officer or officers, or persons performing
similar functions, about the effectiveness of the registrant's disclosure
controls and procedures (as defined in Rule 30a-2(c) under the Act (17 CFR
270.30a-2(c))) based on their evaluation of these controls and procedures as of
a date within 90 days of the filing date of the report that includes the
disclosure required by this paragraph.

The registrant's principal executive officer
and principal financial officer have
concluded that the registrant's disclosure
controls and procedures are effective based
on their evaluation of these controls and
procedures as of a date within 90 days of the
filing date of this report.


(b) Disclose whether or not there were significant changes in the registrant's
internal controls or in other factors that could significantly affect these
controls subsequent to the date of their evaluation, including any corrective
actions with regard to significant deficiencies and material weaknesses.

There were no significant changes in the
registrant's internal control over financial
reporting that occurred during the second
fiscal quarter of the period covered by this
report that have materially affected, or are
reasonably likely to materially affect, the
registrant's internal control over financial
reporting.

The registrant's principal executive officer and principal financial
officer, however, voluntarily are reporting the following information:

In August of 2006 the registrant's investment adviser
enhanced its internal procedures for reporting performance
information required to be included in prospectuses.
Those enhancements involved additional internal controls
over the appropriateness of performance data
generated for this purpose.  Such enhancements were made
following an internal review which identified
prospectuses relating to certain classes of shares of
a limited number of registrants where, inadvertently,
performance information not reflecting the deduction of
applicable sales charges was included. Those prospectuses
were revised, and the revised prospectuses were distributed to
shareholders.


ITEM 12. EXHIBITS.

File the exhibits listed below as part of this Form. Letter or number the
exhibits in the sequence indicated.

(a) Any code of ethics, or amendment thereto, that is the subject of the
disclosure required by Item 2, to the extent that the registrant intends to
satisfy the Item 2 requirements through filing of an exhibit.



(b) A separate certification for each principal executive officer and principal
financial officer of the registrant as required by Rule 30a-2 under the Act
(17 CFR 270.30a-2).

Filed herewith.





                                   SIGNATURES

                          [See General Instruction F]


Pursuant to the requirements of the Securities Exchange Act of 1934 and the
Investment Company Act of 1940, the registrant has duly caused this report to be
signed on its behalf by the undersigned, thereunto duly authorized.


(Registrant) Pioneer Municipal High Income Trust


By (Signature and Title)* /s/ John F. Cogan, Jr.
John F. Cogan, Jr, President

Date June 29, 2009


Pursuant to the requirements of the Securities Exchange Act of 1934 and the
Investment Company Act of 1940, this report has been signed below by the
following persons on behalf of the registrant and in the capacities and on the
dates indicated.


By (Signature and Title)* /s/ John F. Cogan, Jr.
John F. Cogan, Jr., President

Date June 29, 2009


By (Signature and Title)* /s/ Mark Bradley
Mark Bradley, Treasurer

Date June 29, 2009

* Print the name and title of each signing officer under his or her signature.