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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 811-01835

                          Pioneer Series Trust XI
               (Exact name of registrant as specified in charter)


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


            Terrence J. Cullen, 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:  December 31


Date of reporting period:  January 1, 2014 through December 31, 2014


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 STOCKHOLDERS.


                          Pioneer Core
                          Equity Fund

--------------------------------------------------------------------------------
                          Annual Report | December 31, 2014
--------------------------------------------------------------------------------

                          Ticker Symbols:

                          Class A     PIOTX
                          Class C     PCOTX
                          Class Y     PVFYX

                          [LOGO] PIONEER
                                 Investments(R)



                      visit us: us.pioneerinvestments.com


Table of Contents


                                                                           
President's Letter                                                             2

Portfolio Management Discussion                                                4

Portfolio Summary                                                              9

Prices and Distributions                                                      10

Performance Update                                                            11

Comparing Ongoing Fund Expenses                                               14

Schedule of Investments                                                       16

Financial Statements                                                          22

Notes to Financial Statements                                                 29

Report of Independent Registered Public Accounting Firm                       39

Approval of Investment Advisory Agreement                                     40

Trustees, Officers and Service Providers                                      44


                           Pioneer Core Equity Fund | Annual Report | 12/31/14 1


President's Letter

Dear Shareowner,

Today's market environment presents numerous opportunities as well as challenges
for investors. A disparate global economic landscape has formed, with the U.S.
facing prospects for continued growth, while questions abound regarding the
outlook for other regions. Employment, household income, and corporate profits
have been rising in the U.S. and inflation pressures remain low. However, many
countries across Europe as well as Japan face muted growth. In addition, a
variety of factors have clouded the outlook for countries such as Russia and
Brazil and China's investment-driven economy continues to slow.

Monetary policies of major central banks are diverging, reflecting different
economic conditions. With the U.S. economy no longer in need of extraordinary
stimulus, the Federal Reserve Board may be closer to raising short-term interest
rates. Conversely, the European Central Bank and the Bank of Japan are likely to
be adding, not removing, stimulus.

While we anticipate continued growth for the U.S., the outlook is far from
certain, nor is the outlook for other regions necessarily dire. It remains to be
seen how weakness outside the U.S. will affect global growth and whether easing
monetary policies in other regions will spur an economic recovery.

While these economic conditions may lead to increasing volatility in 2015, we
believe the opportunity for investors to earn attractive returns will persist.
However, in an environment where interest rates remain low and equity valuations
have been buoyed by an extended bull market, we believe it is imperative
investors adhere to a disciplined investment approach that is consistent with
one's goals and objectives, being mindful of the tradeoff between risk and
return.

Since 1928 Pioneer's investment professionals have been focused on identifying
and capitalizing on investment opportunities that present themselves in a
variety of ever changing market conditions, including those we face today. We
seek returns consistent with our strategies' stated style and

2 Pioneer Core Equity Fund | Annual Report | 12/31/14


objectives and consistent with our shareholders' expectations, regardless of
market conditions. We believe our shareowners benefit from the experience and
tenure of our investment teams, the insights generated from extensive research
resources and a commitment to prudent risk management designed to mitigate
downside and preserve returns over time.

We encourage you to work with your financial advisor to develop an overall
investment plan that addresses both your short- and long-term goals, and to
implement such a plan in a disciplined manner, as we do when deploying
strategies on behalf of our shareowners.

We greatly appreciate your trust in us in the past and look forward to
continuing to serve you in the future.

Sincerely,

/s/ Lisa M. Jones

Lisa M. Jones
President and CEO
Pioneer Investment Management USA, Inc.

Any information in this shareowner report regarding market or economic trends or
the factors influencing the Fund's historical or future performance are
statements of opinion 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 Core Equity Fund | Annual Report | 12/31/14 3


Portfolio Management Discussion | 12/31/14

The domestic equity market generated positive performance during 2014, helped by
growing evidence that the U.S. economic recovery finally had started to generate
consistent and impressive gains in employment, without adding to inflationary
pressures. In the following interview, Paul Cloonan and John Peckham discuss the
market environment and the factors that influenced the performance of Pioneer
Core Equity Fund during 12-month period ended December 31, 2014. Mr. Cloonan,
Senior Vice President, Co-Head of Equity Research, U.S., and a portfolio manager
at Pioneer, and Mr. Peckham, CFA, Senior Vice President, Co-Head of Equity
Research, U.S., and a portfolio manager at Pioneer, are responsible for the
day-to-day management of the Fund, along with James Moynihan, a vice president
and equity research analyst at Pioneer.

Q    How did the Fund perform during the 12-month period ended December 31,
     2014?

A    Pioneer Core Equity Fund's Class A shares returned 10.44% at net asset
     value during the 12-month period ended December 31 2014, while the Fund's
     benchmark, the Standard & Poor's 500 Index (the S&P 500), returned 13.66%.
     During the same period, the average return of the 857 mutual funds in
     Lipper's Large-Cap Core Funds category was 11.32%, and the average return
     of the 1,568 mutual funds in Morningstar's Large Blend Fund category was
     10.96%.

Q    How would you describe the investment environment for equities during the
     12-month period ended December 31, 2014?

A    The domestic stock market registered healthy gains during the year based on
     growing confidence in the strength and durability of the U.S. economic
     recovery. While the year began with a decline in gross domestic product
     (GDP) in the first quarter, the economy then accelerated, with GDP growing
     at a 4.6% annual rate in the second calendar quarter and a 5.0% rate in the
     third quarter, with widespread evidence of a continuing - if slightly less
     robust - expansion in the fourth quarter. Importantly, the employment
     situation, which had appeared stagnant early in economic recovery, finally
     started to improve, with the economy producing an average of 250,000 new
     jobs each month by the end of the 2014. Meanwhile, the housing market,
     which had crashed as the economy fell into recession in 2008 and 2009, also
     showed steady improvement.

     While the equity market made gains throughout the 12-month period,
     volatility also increased beginning in September 2014. One factor
     contributing to the volatility was the end of the quantitative easing (QE)
     policies of the U.S. Federal Reserve System (the Fed), which had involved

4 Pioneer Core Equity Fund | Annual Report | 12/31/14


     injecting liquidity into the capital markets through monthly purchases of
     Treasuries and government-backed mortgage securities in the open market.
     Late in the year, several factors also combined to drive market volatility,
     including: rising global geopolitical risks, particularly in the Middle
     East and Eastern Europe; disappointing economic growth trends in Europe,
     Japan and China; and collapsing prices of commodities, especially oil. In
     addition, the U.S. dollar strengthened against most foreign currencies
     during the period.

     For the full 12 months, stocks in the utilities sector produced the
     strongest average performance, followed by stocks in the health care
     sector. Energy stocks registered the poorest results by far, with stocks of
     oil-related companies falling hard as oil prices collapsed.

Q    What types of investments tended to have the greatest influence on the
     Fund's benchmark-relative performance during the 12-month period ended
     December 31, 2014?

A    The Fund's exposures to the energy and the financials sectors were the main
     reasons for its underperformance relative to the S&P 500 during the period,
     while investments in health care provided the greatest support to relative
     returns.

     In energy, the collapse in crude oil prices undercut the performance of
     several of the portfolio's holdings in the energy exploration-and-
     production (E&P) and oil services areas. We liquidated the Fund's
     investments in three E&P holdings that were among the most disappointing
     performers during the period: Whiting Petroleum; Southwestern Energy; and
     Kodiak Oil & Gas.

     Among holdings in the financials sector, diversified banking firms Bank of
     America and Citigroup underperformed and detracted from the Fund's
     benchmark-relative results. In addition, benchmark-relative performance was
     hurt by not owning certain positions that are part of the S&P 500. In
     particular, we largely avoided insurers, which performed well during the
     period, and did not hold any shares in the portfolio of either diversified
     financials company Berkshire Hathaway or banking corporation Wells Fargo;
     those decisions hurt benchmark-relative results as each company turned in
     very strong performance during the period. Another detractor from the
     Fund's benchmark-relative returns in financials was the portfolio's
     underweight in real estate investment trusts (REITs), which are interest-
     rate-sensitive organizations that showed strong improvement during 2014.
     With interest rates declining over the 12-month period, REITs were an
     increasingly attractive alternative to government or corporate bonds for
     investors seeking current income.

                           Pioneer Core Equity Fund | Annual Report | 12/31/14 5



     Other holdings that detracted from the Fund's performance during the period
     included Nu Skin Enterprises, a global marketer of skin-care products with
     heavy exposure to the Chinese market. Shares of Nu Skin fell precipitously
     during the period following a Chinese government investigation of the
     company's sales practices. While the investigation was resolved with a
     relatively small fine, the company was slow to regain its earlier, lost
     momentum.

     On the positive side, good stock selection and an overweight portfolio
     position in health care boosted the Fund's returns relative to the
     benchmark. During the period, the sector featured a broad array of stellar
     performers among pharmaceutical, health services, and health care equipment
     corporations. Within health care, the Fund's holdings of Covidien and
     Actavis produced particularly strong results. Covidien, a producer of
     medical equipment and other medical products, was the biggest contributor
     to benchmark-relative performance within the sector as the company's share
     price appreciated significantly after it received a takeover offer from
     medical device manufacturer Medtronic. Actavis is a specialty and generic
     pharmaceutical company that successfully grew its earnings during the
     period, partly as the result of several previous acquisitions.

     Within the consumer discretionary sector, two significant contributors to
     relative performance were the Fund's positions in hotel and resort operator
     Marriott International and retail hardware chain Lowe's. Marriott's high
     occupancy rates and strong pricing trends led to accelerating earnings
     growth during the period, while Lowe's benefited from the recovery in the
     housing industry.

Q    Were any notable changes made in the Fund's portfolio during the 12-month
     period ended December 31, 2014?

A    We continued to look for new investment opportunities for the Fund during
     the period, even as we sold positions in several companies that either had
     done well, had deteriorating prospects, or had produced disappointing
     results. We made significant changes among the portfolio's energy holdings,
     notably adding a position late in the period in ExxonMobil, which we
     thought had a more diversified asset base that was better able to withstand
     the effects of declining oil prices. As we did so, we eliminated positions
     in several oil services and energy E&P companies that were more directly
     hurt by collapsing commodity prices. The sales included shares of: Superior
     Energy, Kodiak Oil & Gas, Halliburton Company, Pioneer Natural Resources,
     and Whiting Petroleum. Earlier in the Fund's fiscal year, we also had sold
     positions in Occidental Petroleum and Marathon Oil.

6 Pioneer Core Equity Fund | Annual Report | 12/31/14


     We made a number of changes among the Fund's holdings in financials as
     well. Early in the period, we sold investments in Keycorp, Goldman Sachs,
     ACE, Walter Investment Management, BB&T, and insurer Aflac. Financial
     companies that we added to the portfolio during the period included Voya
     Financial and Lazard.

     In health care, we sold the Fund's holdings of pharmaceutical company
     Pfizer and diversified corporation Johnson & Johnson late in the period,
     while adding positions in pharmaceutical companies Teva Pharmaceuticals and
     Mallinckrodt. Earlier, we had sold the Fund's investment in AstraZeneca and
     established a position in Merck.

     We also liquidated positions in Time Warner, Estee Lauder and Dick's
     Sporting Goods, while adding investments in -- among others -- Facebook and
     Host Hotels and Resorts.

Q    Did you make investments in any derivative securities during the 12-month
     period ended December 31, 2014?

A    No, we did not use any derivatives in the Fund's portfolio during the
     period.

Q    What is your investment outlook?

A    We believe economic growth in the U.S. should remain stable, which would be
     positive for equity values.

     As the employment market continues to improve, consumer spending also
     should stabilize. Meanwhile, we believe inflationary pressures are likely
     to remain muted, in part because of weak commodity prices and the strong
     U.S. dollar. The domestic economy also should be helped by improvements in
     the U.S. fiscal deficit. That, in turn, could lead to less pressure on
     lawmakers to either reduce government spending or to raise taxes. Although
     the end of the Fed's QE policy may lead to more volatility in equity
     prices, we anticipate that overall financial conditions will remain benign.
     The absence of any significant inflationary forces also may discourage the
     Fed from raising short-term interest rates substantially.

     While the outlook in the U.S. appears favorable, risks from overseas could
     affect the domestic economy. Growth in China is slowing as the government
     moves to cut back on the expansion of credit, while Russia's actions in the
     Ukraine and the resulting economic sanctions imposed by the West
     potentially could affect the stability and growth of the global economy.

                           Pioneer Core Equity Fund | Annual Report | 12/31/14 7


     Nevertheless, we assume that if the challenges in the emerging markets do
     not worsen, the outlook for U.S. equities will remain healthy. Valuations
     in most stock groups remain relatively reasonable, while corporate balance
     sheets and cash flows continue to be solid. Those factors could lead to
     actions that tend to support equity performance, including mergers and
     acquisitions, share repurchases, and increases in stock dividends*.

     Consistent with our long-term investment discipline for the Fund, we will
     continue to focus on stock picking, a process which emphasizes bottom-up,
     fundamental analysis. We believe this approach is durable and repeatable
     and can bring reasonable investment performance in a variety of market
     conditions and at various stages of the economic cycle.

Please refer to the Schedule of Investments on pages 16-21 for a full listing of
Fund securities.

At times, the Fund'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.

These risks may increase share price volatility.

Before investing, consider the product's investment objectives, risks, charges
and expenses. Contact your advisor or Pioneer Investments for a prospectus or
summary prospectus containing this information. Read it carefully.

Any information in this shareholder report regarding market or economic trends
or the factors influencing the Fund's historical or future performance are
statements of opinion as of the date of this report. Past performance is no
guarantee of future results.

* Dividends are not guaranteed.

8 Pioneer Core Equity Fund | Annual Report | 12/31/14


Portfolio Summary | 12/31/14

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

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



                                                                        
U.S. Common Stocks                                                         94.2%
International Common Stocks                                                 5.2%
Depository Receipts for International Stocks                                0.6%


Sector Distribution
--------------------------------------------------------------------------------
(As a percentage of equity holdings)

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



                                                                        
Information Technology                                                     20.3%
Financials                                                                 16.8%
Health Care                                                                15.4%
Consumer Discretionary                                                     11.9%
Industrials                                                                11.3%
Consumer Staples                                                            9.6%
Energy                                                                      6.5%
Utilities                                                                   3.1%
Materials                                                                   2.7%
Telecommunication Services                                                  2.4%


10 Largest Holdings
--------------------------------------------------------------------------------
(As a percentage of equity holdings)*



                                                                        
 1.   Apple, Inc.                                                          4.48%
--------------------------------------------------------------------------------
 2.   Microsoft Corp.                                                      3.27
--------------------------------------------------------------------------------
 3.   Exxon Mobil Corp.                                                    2.36
--------------------------------------------------------------------------------
 4.   Bank of America Corp.                                                2.15
--------------------------------------------------------------------------------
 5.   AbbVie, Inc.                                                         2.12
--------------------------------------------------------------------------------
 6.   Honeywell International, Inc.                                        2.07
--------------------------------------------------------------------------------
 7.   Verizon Communications, Inc.                                         2.01
--------------------------------------------------------------------------------
 8.   Citigroup, Inc.                                                      2.01
--------------------------------------------------------------------------------
 9.   Merck & Co., Inc.                                                    1.98
--------------------------------------------------------------------------------
10.   Lowe's Companies, Inc.                                               1.95
--------------------------------------------------------------------------------


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

                           Pioneer Core Equity Fund | Annual Report | 12/31/14 9


Prices and Distributions | 12/31/14

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



--------------------------------------------------------------------------------
        Class                      12/31/14                        12/31/13*
--------------------------------------------------------------------------------
                                                              
          A                         $17.18                          $15.70
--------------------------------------------------------------------------------
          C                         $15.48                          $14.19
--------------------------------------------------------------------------------
          Y                         $17.34                          $15.85
--------------------------------------------------------------------------------


Distributions per Share: 1/1/14 - 12/31/14
--------------------------------------------------------------------------------



--------------------------------------------------------------------------------
                    Net Investment       Short-Term           Long-Term
        Class           Income          Capital Gains       Capital Gains
--------------------------------------------------------------------------------
                                                       
          A             $0.1619             $   --              $    --
--------------------------------------------------------------------------------
          C             $0.0620             $   --              $    --
--------------------------------------------------------------------------------
          Y             $0.2165             $   --              $    --
--------------------------------------------------------------------------------


*    The Fund acquired the assets and liabilities of Pioneer Research Fund (the
     "predecessor fund") on June 7, 2013 (the "reorganization"). As a result of
     the reorganization, the predecessor fund's performance and financial
     history became the performance and financial history of the Fund.
     Historical per-share amounts prior to June 7, 2013 have been adjusted to
     reflect the conversion ratios used for the reorganization.

Index Definition
--------------------------------------------------------------------------------
The Standard & Poor's 500 Index is an unmanaged, commonly used measure of the
broad U.S. stock market. Index returns are calculated monthly, assume
reinvestment of dividends and, unlike Fund returns, do not reflect any fees,
expenses or sales charges. It is not possible to invest directly in an index.

The  index defined here pertains to the "Value of $10,000 Investment" and "Value
of $5 Million Investment" charts on pages 11-13.

10 Pioneer Core Equity Fund | Annual Report | 12/31/14


Performance Update | 12/31/14                                     Class A Shares

Investment Returns
--------------------------------------------------------------------------------
The mountain chart on the right shows the change in value of a $10,000
investment made in Class A shares of Pioneer Core Equity Fund at public offering
price during the periods shown, compared to that of the Standard & Poor's 500
Index.



Average Annual Total Returns
(As of December 31, 2014)
--------------------------------------------------------------------------------
                      Net             Public
                      Asset           Offering        S&P
                      Value           Price           500
Period                (NAV)           (POP)           Index
--------------------------------------------------------------------------------
                                             
10 Years               7.88%           7.24%           7.67%
5 Years               14.10           12.76           15.44
1 Year                10.44            4.08           13.66
--------------------------------------------------------------------------------


Expense Ratio
(Per prospectus dated May 1, 2014)
--------------------------------------------------------------------------------
                      Gross
--------------------------------------------------------------------------------
                   
                      0.99%
--------------------------------------------------------------------------------


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

Value of $10,000 Investment



                                      Pioneer Core             Standard & Poor's
                                      Equity Fund              500 Index
                                                         
12/31/2004                            $ 9,425                  $10,000
12/31/2005                            $10,103                  $10,491
12/31/2006                            $11,629                  $12,146
12/31/2007                            $12,441                  $12,813
12/31/2008                            $ 8,059                  $ 8,074
12/31/2009                            $10,405                  $10,211
12/31/2010                            $12,026                  $11,751
12/31/2011                            $12,143                  $11,996
12/31/2012                            $13,905                  $13,914
12/31/2013                            $18,219                  $18,418
12/31/2014                            $20,121                  $20,935


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

The performance data quoted represents past performance, which is no guarantee
of future results. Investment return and principal value will fluctuate, and
shares, when redeemed, may be worth more or less than their original cost.

NAV results represent the percent change in net asset value per share. Returns
would have been lower had sales charges been reflected. POP returns reflect
deduction of maximum 5.75% sales charge. All results are historical and assume
the reinvestment of dividends and capital gains. Other share classes are
available for which performance and expenses will differ.

Performance results reflect any applicable expense waivers in effect during the
periods shown. Without such waivers Fund performance would be lower. Waivers may
not be in effect for all funds. Certain fee waivers are contractual through a
specified period. Otherwise, fee waivers can be rescinded at any time. See the
prospectus and financial statements for more information.

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

The Fund acquired the assets and liabilities of Pioneer Research Fund ("the
predecessor fund") on June 7, 2013. As a result of the reorganization, the
predecessor fund's performance and financial history became the performance and
financial history of the Fund. The performance of Class A shares of the Fund is
the performance of Class A shares of the predecessor fund for periods prior to
the reorganization, and has not been restated to reflect any differences in
expenses.

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 11


Performance Update | 12/31/14                                     Class C Shares

Investment Returns
--------------------------------------------------------------------------------
The mountain chart on the right shows the change in value of a $10,000
investment made in Class C shares of Pioneer Core Equity Fund for the periods
shown, compared to that of the Standard & Poor's 500 Index.



Average Annual Total Returns
(As of December 31, 2014)
--------------------------------------------------------------------------------
                                                      S&P
                      If              If              500
Period                Held            Redeemed        Index
--------------------------------------------------------------------------------
                                             
10 Years               6.93%           6.93%           7.67%
5 Years               13.07           13.07           15.44
1 Year                 9.52            9.52           13.66
--------------------------------------------------------------------------------


Expense Ratio
(Per prospectus dated May 1, 2014)
--------------------------------------------------------------------------------
                      Gross
--------------------------------------------------------------------------------
                   
                      1.92%
--------------------------------------------------------------------------------


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

Value of $10,000 Investment



                                      Pioneer Core             Standard & Poor's
                                      Equity Fund              500 Index
                                                         
12/31/2004                            $10,000                  $10,000
12/31/2005                            $10,617                  $10,491
12/31/2006                            $12,108                  $12,146
12/31/2007                            $12,858                  $12,813
12/31/2008                            $ 8,265                  $ 8,074
12/31/2009                            $10,573                  $10,211
12/31/2010                            $12,109                  $11,751
12/31/2011                            $12,122                  $11,996
12/31/2012                            $13,742                  $13,914
12/31/2013                            $17,839                  $18,418
12/31/2014                            $19,537                  $20,935


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

The performance data quoted represents past performance, which is no guarantee
of future results. Investment return and principal value will fluctuate, and
shares, when redeemed, may be worth more or less than their original cost.

Class C shares held for less than one year are also subject to a 1% contingent
deferred sales charge (CDSC). If you paid a 1% sales charge, your returns would
be lower than those shown above. "If Held" results represent the percent change
in net asset value per share. Returns would have been lower had sales charges
been reflected. All results are historical and assume the reinvestment of
dividends and capital gains. Other share classes are available for which
performance and expenses will differ.

Performance results reflect any applicable expense waivers in effect during the
periods shown. Without such waivers Fund performance would be lower. Waivers may
not be in effect for all funds. Certain fee waivers are contractual through a
specified period. Otherwise, fee waivers can be rescinded at any time. See the
prospectus and financial statements for more information.

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

The Fund acquired the assets and liabilities of Pioneer Research Fund ("the
predecessor fund") on June 7, 2013. As a result of the reorganization, the
predecessor fund's performance and financial history became the performance and
financial history of the Fund. The performance of Class C shares of the Fund is
the performance of Class C shares of the predecessor fund for periods prior to
the reorganization, and has not been restated to reflect any differences in
expenses.

12 Pioneer Core Equity Fund | Annual Report | 12/31/14


Performance Update | 12/31/14                                     Class Y Shares

Investment Returns
--------------------------------------------------------------------------------
The mountain chart on the right shows the change in value of a $5 million
investment made in Class Y shares of Pioneer Core Equity Fund during the periods
shown, compared to that of the Standard & Poor's 500 Index.



Average Annual Total Returns
(As of December 31, 2014)
--------------------------------------------------------------------------------
                                                      S&P
                      If              If              500
Period                Held            Redeemed        Index
--------------------------------------------------------------------------------
                                             
10 Years               8.19%           8.19%           7.67%
5 Years               14.42           14.42           15.44
1 Year                10.75           10.75           13.66
--------------------------------------------------------------------------------


Expense Ratio
(Per prospectus dated May 1, 2014)
--------------------------------------------------------------------------------
                      Gross
--------------------------------------------------------------------------------
                   
                      0.75%
--------------------------------------------------------------------------------


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

Value of $5 Million Investment



                                      Pioneer Core             Standard & Poor's
                                      Equity Fund              500 Index
                                                         
12/31/2004                            $ 5,000,000              $ 5,000,000
12/31/2005                            $ 5,367,504              $ 5,245,391
12/31/2006                            $ 6,188,222              $ 6,073,169
12/31/2007                            $ 6,656,097              $ 6,406,558
12/31/2008                            $ 4,329,301              $ 4,036,754
12/31/2009                            $ 5,604,829              $ 5,105,337
12/31/2010                            $ 6,495,576              $ 5,875,431
12/31/2011                            $ 6,573,679              $ 5,998,091
12/31/2012                            $ 7,547,359              $ 6,957,038
12/31/2013                            $ 9,924,356              $ 9,209,149
12/31/2014                            $10,990,865              $10,467,483


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

The performance data quoted represents past performance, which is no guarantee
of future results. Investment return and principal value will fluctuate, and
shares, when redeemed, may be worth more or less than their original cost.

The Fund acquired the assets and liabilities of Pioneer Research Fund ("the
predecessor fund") on June 7, 2013. As a result of the reorganization, the
predecessor fund's performance and financial history became the performance and
financial history of the Fund. The performance of Class Y shares of the Fund is
the performance of Class Y shares of the predecessor fund for periods prior to
the reorganization, and has not been restated to reflect any differences in
expenses.

Performance shown for periods prior to the inception of Class Y shares of the
predecessor fund on August 11, 2004, reflects the NAV performance of the
predecessor fund's Class A shares. The performance does not reflect differences
in expenses, including the Rule 12b-1 fees applicable to Class A shares. Since
fees for Class A shares are generally higher than those of Class Y shares, the
performance for Class Y shares of the predecessor fund prior to their inception
on August 11, 2004, would have been higher than that shown. Class Y shares are
not subject to sales charges and are available for limited groups of eligible
investors, including institutional investors. All results are historical and
assume the reinvestment of dividends and capital gains. Other share classes are
available for which performance and expenses will differ.

Performance results reflect any applicable expense waivers in effect during the
periods shown. Without such waivers Fund performance would be lower. Waivers may
not be in effect for all funds. Certain fee waivers are contractual through a
specified period. Otherwise, fee waivers can be rescinded at any time. See the
prospectus and financial statements for more information.

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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 13


Comparing Ongoing Fund Expenses

As a shareowner in the Fund, you incur two types of costs:

(1) ongoing costs, including management fees, distribution and/or service
    (12b-1) fees, and other Fund expenses; and

(2) transaction costs, including sales charges (loads) on purchase payments.

This example is intended to help you understand your ongoing expenses (in
dollars) of investing in the Fund and to compare these costs with the ongoing
costs of investing in other mutual funds. The example is based on an investment
of $1,000 at the beginning of the Fund's latest six-month period and held
throughout the six months.

Using the Tables
--------------------------------------------------------------------------------
Actual Expenses

The first table below provides information about actual account values and
actual expenses. You may use the information in this table, together with the
amount you invested, to estimate the expenses that you paid over the period as
follows:

(1) Divide your account value by $1,000
    Example: an $8,600 account value (divided by) $1,000 = 8.6

(2) Multiply the result in (1) above by the corresponding share class's number
    in the third row under the heading entitled "Expenses Paid During Period" to
    estimate the expenses you paid on your account during this period.

Expenses Paid on a $1,000 Investment in Pioneer Core Equity Fund

Based on actual returns from July 1, 2014 through December 31, 2014.



--------------------------------------------------------------------------------
Share Class                           A                  C                 Y
--------------------------------------------------------------------------------
                                                              
Beginning Account Value           $1,000.00          $1,000.00         $1,000.00
on 7/1/14
--------------------------------------------------------------------------------
Ending Account Value              $1,045.83          $1,041.66         $1,047.98
(after expenses)
on 12/31/14
--------------------------------------------------------------------------------
Expenses Paid                     $    4.85          $    9.31         $    3.25
During Period*
--------------------------------------------------------------------------------


*   Expenses are equal to the Fund's annualized expense ratio of 0.94%, 1.81%,
    and 0.63% for Class A, Class C, and Class Y, respectively, multiplied by the
    average account value over the period, multiplied by 184/365 (to reflect the
    one-half year period).

14 Pioneer Core Equity Fund | Annual Report | 12/31/14


Hypothetical Example for Comparison Purposes

The table below provides information about hypothetical account values and
hypothetical expenses based on the Fund's actual expense ratio and an assumed
rate of return of 5% per year before expenses, which is not the Fund's actual
return. The hypothetical account values and expenses may not be used to estimate
the actual ending account balance or expenses you paid for the period.

You may use this information to compare the ongoing costs of investing in the
Fund and other funds. To do so, compare this 5% hypothetical example with the 5%
hypothetical examples that appear in the shareholder reports of the other funds.

Please note that the expenses shown in the tables are meant to highlight your
ongoing costs only and do not reflect any transaction costs, such as sales
charges (loads) that are charged at the time of the transaction. Therefore, the
table below is useful in comparing ongoing costs only and will not help you
determine the relative total costs of owning different funds. In addition, if
these transaction costs were included, your costs would have been higher.

Expenses Paid on a $1,000 Investment in Pioneer Core Equity Fund

Based on a hypothetical 5% per year return before expenses, reflecting the
period from July 1, 2014 through December 31, 2014.



--------------------------------------------------------------------------------
Share Class                           A                  C                 Y
--------------------------------------------------------------------------------
                                                              
Beginning Account Value           $1,000.00          $1,000.00         $1,000.00
on 7/1/14
--------------------------------------------------------------------------------
Ending Account Value              $1,020.47          $1,016.08         $1,022.03
(after expenses)
on 12/31/14
--------------------------------------------------------------------------------
Expenses Paid                     $    4.79          $    9.20         $    3.21
During Period*
--------------------------------------------------------------------------------


*   Expenses are equal to the Fund's annualized expense ratio of 0.94%, 1.81%,
    and 0.63% for Class A, Class C, and Class Y, respectively, multiplied by the
    average account value over the period, multiplied by 184/365 (to reflect the
    one-half year period).

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 15


Schedule of Investments | 12/31/14



-------------------------------------------------------------------------------------
Shares                                                                 Value
-------------------------------------------------------------------------------------
                                                                 
                COMMON STOCKS -- 99.4%
                ENERGY -- 6.5%
                Integrated Oil & Gas -- 2.4%
     427,814    Exxon Mobil Corp.                                      $   39,551,404
-------------------------------------------------------------------------------------
                Oil & Gas Exploration & Production -- 3.4%
     313,502    Cabot Oil & Gas Corp.                                  $    9,282,794
     336,083    ConocoPhillips                                             23,209,892
     268,067    EOG Resources, Inc.                                        24,680,929
                                                                       --------------
                                                                       $   57,173,615
-------------------------------------------------------------------------------------
                Oil & Gas Refining & Marketing -- 0.7%
     137,216    Marathon Petroleum Corp.*                              $   12,385,116
                                                                       --------------
                Total Energy                                           $  109,110,135
-------------------------------------------------------------------------------------
                MATERIALS -- 2.7%
                Commodity Chemicals -- 0.7%
     147,393    LyondellBasell Industries NV                           $   11,701,530
-------------------------------------------------------------------------------------
                Fertilizers & Agricultural Chemicals -- 1.4%
     196,048    Monsanto Co.                                           $   23,421,855
-------------------------------------------------------------------------------------
                Specialty Chemicals -- 0.6%
     103,548    Ecolab, Inc.                                           $   10,822,837
                                                                       --------------
                Total Materials                                        $   45,946,222
-------------------------------------------------------------------------------------
                CAPITAL GOODS -- 7.9%
                Aerospace & Defense -- 3.1%
     347,456    Honeywell International, Inc.                          $   34,717,804
     151,373    United Technologies Corp.                                  17,407,895
                                                                       --------------
                                                                       $   52,125,699
-------------------------------------------------------------------------------------
                Electrical Components & Equipment -- 1.5%
     374,253    Eaton Corp. Plc                                        $   25,434,234
-------------------------------------------------------------------------------------
                Construction & Farm Machinery & Heavy Trucks -- 0.6%
      71,537    Cummins, Inc.                                          $   10,313,489
-------------------------------------------------------------------------------------
                Industrial Machinery -- 2.7%
     399,668    Ingersoll-Rand Plc                                     $   25,334,955
     148,759    Parker-Hannifin Corp.                                      19,182,473
                                                                       --------------
                                                                       $   44,517,428
                                                                       --------------
                Total Capital Goods                                    $  132,390,850
-------------------------------------------------------------------------------------
                TRANSPORTATION -- 3.4%
                Airlines -- 1.9%
     588,183    American Airlines Group, Inc.                          $   31,544,254
-------------------------------------------------------------------------------------
                Railroads -- 1.5%
     216,639    Union Pacific Corp.                                    $   25,808,204
                                                                       --------------
                Total Transportation                                   $   57,352,458
-------------------------------------------------------------------------------------


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

16 Pioneer Core Equity Fund | Annual Report | 12/31/14




-------------------------------------------------------------------------------------
Shares                                                                 Value
-------------------------------------------------------------------------------------
                                                                 
                CONSUMER DURABLES & APPAREL -- 0.5%
                Apparel, Accessories & Luxury Goods -- 0.5%
      70,845    PVH Corp.                                              $    9,080,204
                                                                       --------------
                Total Consumer Durables & Apparel                      $    9,080,204
-------------------------------------------------------------------------------------
                CONSUMER SERVICES -- 2.3%
                Hotels, Resorts & Cruise Lines -- 1.3%
     271,172    Marriott International, Inc.                           $   21,159,551
-------------------------------------------------------------------------------------
                Restaurants -- 1.0%
     208,062    Starbucks Corp.                                        $   17,071,487
                                                                       --------------
                Total Consumer Services                                $   38,231,038
-------------------------------------------------------------------------------------
                MEDIA -- 4.7%
                Broadcasting -- 0.7%
     200,777    CBS Corp. (Class B)                                    $   11,110,999
-------------------------------------------------------------------------------------
                Cable & Satellite -- 2.3%
     534,175    Comcast Corp.                                          $   30,987,492
      57,539    Time Warner Cable, Inc.                                     8,749,380
                                                                       --------------
                                                                       $   39,736,872
-------------------------------------------------------------------------------------
                Movies & Entertainment -- 1.7%
     308,716    The Walt Disney Co.                                    $   29,077,960
                                                                       --------------
                Total Media                                            $   79,925,831
-------------------------------------------------------------------------------------
                RETAILING -- 4.4%
                Department Stores -- 1.0%
     250,160    Macy's, Inc.                                           $   16,448,020
-------------------------------------------------------------------------------------
                Apparel Retail -- 1.5%
     257,096    Ross Stores, Inc.                                      $   24,233,869
-------------------------------------------------------------------------------------
                Home Improvement Retail -- 1.9%
     473,975    Lowe's Companies, Inc.                                 $   32,609,480
                                                                       --------------
                Total Retailing                                        $   73,291,369
-------------------------------------------------------------------------------------
                FOOD & STAPLES RETAILING -- 1.7%
                Drug Retail -- 1.7%
     301,067    CVS Health Corp.                                       $   28,995,763
                                                                       --------------
                Total Food & Staples Retailing                         $   28,995,763
-------------------------------------------------------------------------------------
                FOOD, BEVERAGE & TOBACCO -- 7.3%
                Brewers -- 1.2%
     265,172    Molson Coors Brewing Co. (Class B)                     $   19,760,617
-------------------------------------------------------------------------------------
                Soft Drinks -- 1.3%
     232,357    PepsiCo., Inc.                                         $   21,971,678
-------------------------------------------------------------------------------------


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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 17


Schedule of Investments | 12/31/14 (continued)



-------------------------------------------------------------------------------------
Shares                                                                 Value
-------------------------------------------------------------------------------------
                                                                 
                Packaged Foods & Meats -- 3.3%
     220,313    Campbell Soup Co.                                      $    9,693,772
      98,606    Keurig Green Mountain, Inc.                                13,054,941
     521,007    Mondelez International, Inc.                               18,925,579
     143,965    The Hershey Co.                                            14,962,282
                                                                       --------------
                                                                       $   56,636,574
-------------------------------------------------------------------------------------
                Tobacco -- 1.5%
     398,878    Lorillard, Inc.                                        $   25,105,381
                                                                       --------------
                Total Food, Beverage & Tobacco                         $  123,474,250
-------------------------------------------------------------------------------------
                HOUSEHOLD & PERSONAL PRODUCTS -- 0.6%
                Personal Products -- 0.6%
     227,319    Nu Skin Enterprises, Inc.                              $    9,933,840
                                                                       --------------
                Total Household & Personal Products                    $    9,933,840
-------------------------------------------------------------------------------------
                HEALTH CARE EQUIPMENT & SERVICES -- 6.0%
                Health Care Equipment -- 1.1%
     189,104    Covidien Plc                                           $   19,341,557
-------------------------------------------------------------------------------------
                Health Care Distributors -- 1.6%
     329,209    Cardinal Health, Inc.                                  $   26,577,043
-------------------------------------------------------------------------------------
                Health Care Services -- 1.7%
     133,210    DaVita HealthCare Partners, Inc.*                      $   10,089,325
     210,529    Express Scripts Holding Co.*                               17,825,490
                                                                       --------------
                                                                       $   27,914,815
-------------------------------------------------------------------------------------
                Managed Health Care -- 1.6%
     150,227    Aetna, Inc.                                            $   13,344,664
      91,719    Humana, Inc.                                               13,173,600
                                                                       --------------
                                                                       $   26,518,264
                                                                       --------------
                Total Health Care Equipment & Services                 $  100,351,679
-------------------------------------------------------------------------------------
                PHARMACEUTICALS, BIOTECHNOLOGY &
                LIFE SCIENCES -- 9.4%
                Biotechnology -- 3.8%
     201,648    Celgene Corp.*                                         $   22,556,345
     308,376    Gilead Sciences, Inc.*                                     29,067,522
     108,420    Vertex Pharmaceuticals, Inc.*                              12,880,296
                                                                       --------------
                                                                       $   64,504,163
-------------------------------------------------------------------------------------
                Pharmaceuticals -- 5.6%
     543,513    AbbVie, Inc.                                           $   35,567,491
     164,533    Mallinckrodt Plc*                                          16,293,703
     583,133    Merck & Co., Inc.                                          33,116,123
     149,658    Teva Pharmaceutical Industries, Ltd. (A.D.R.)               8,606,832
                                                                       --------------
                                                                       $   93,584,149
                                                                       --------------
                Total Pharmaceuticals, Biotechnology & Life Sciences   $  158,088,312
-------------------------------------------------------------------------------------


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

18 Pioneer Core Equity Fund | Annual Report | 12/31/14




-------------------------------------------------------------------------------------
Shares                                                                 Value
-------------------------------------------------------------------------------------
                                                                 
                BANKS -- 6.4%
                Diversified Banks -- 4.1%
   2,011,261    Bank of America Corp.                                  $   35,981,459
     621,593    Citigroup, Inc.                                            33,634,397
                                                                       --------------
                                                                       $   69,615,856
-------------------------------------------------------------------------------------
                Regional Banks -- 2.3%
   1,218,125    Regions Financial Corp.                                $   12,863,400
     276,614    The PNC Financial Services Group, Inc.                     25,235,495
                                                                       --------------
                                                                       $   38,098,895
                                                                       --------------
                Total Banks                                            $  107,714,751
-------------------------------------------------------------------------------------
                DIVERSIFIED FINANCIALS -- 7.1%
                Other Diversified Financial Services -- 1.0%
     403,235    Voya Financial, Inc.                                   $   17,089,099
-------------------------------------------------------------------------------------
                Specialized Finance -- 1.6%
      49,206    Intercontinental Exchange, Inc.                        $   10,790,384
     325,946    The NASDAQ OMX Group, Inc.                                 15,632,370
                                                                       --------------
                                                                       $   26,422,754
-------------------------------------------------------------------------------------
                Consumer Finance -- 1.0%
     273,931    Discover Financial Services, Inc.                      $   17,939,741
-------------------------------------------------------------------------------------
                Asset Management & Custody Banks -- 1.4%
      74,128    Affiliated Managers Group, Inc.*                       $   15,732,927
     291,236    The Carlyle Group LP                                        8,008,990
                                                                       --------------
                                                                       $   23,741,917
-------------------------------------------------------------------------------------
                Investment Banking & Brokerage -- 2.1%
     307,093    Lazard, Ltd.                                           $   15,363,863
     502,903    Morgan Stanley Co.                                         19,512,636
                                                                       --------------
                                                                       $   34,876,499
                                                                       --------------
                Total Diversified Financials                           $  120,070,010
-------------------------------------------------------------------------------------
                INSURANCE -- 2.0%
                Multi-line Insurance -- 1.2%
     475,433    The Hartford Financial Services Group, Inc.            $   19,820,802
-------------------------------------------------------------------------------------
                Property & Casualty Insurance -- 0.8%
     206,002    The Allstate Corp.                                     $   14,471,640
                                                                       --------------
                Total Insurance                                        $   34,292,442
-------------------------------------------------------------------------------------
                REAL ESTATE -- 1.2%
                Hotel & Resort REIT -- 1.2%
     825,507    Host Hotels & Resorts, Inc.                            $   19,622,301
                                                                       --------------
                Total Real Estate                                      $   19,622,301
-------------------------------------------------------------------------------------
                SOFTWARE & SERVICES -- 11.0%
                Internet Software & Services -- 6.2%
     402,134    eBay, Inc.*                                            $   22,567,760
     279,944    Facebook, Inc.*                                            21,841,231


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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 19


Schedule of Investments | 12/31/14 (continued)



-------------------------------------------------------------------------------------
Shares                                                                 Value
-------------------------------------------------------------------------------------
                                                                 
                Internet Software & Services -- (continued)
      44,657    Google, Inc. (Class A)*                                $   23,697,684
      24,130    Google, Inc. (Class C)                                     12,702,032
     466,080    Yahoo!, Inc.*                                              23,541,701
                                                                       --------------
                                                                       $  104,350,408
-------------------------------------------------------------------------------------
                Data Processing & Outsourced Services -- 1.6%
     103,313    Visa, Inc.                                             $   27,088,669
-------------------------------------------------------------------------------------
                Systems Software -- 3.2%
   1,177,422    Microsoft Corp.                                        $   54,691,252
                                                                       --------------
                Total Software & Services                              $  186,130,329
-------------------------------------------------------------------------------------
                TECHNOLOGY HARDWARE & EQUIPMENT -- 7.5%
                Communications Equipment -- 1.3%
     166,428    F5 Networks, Inc.*                                     $   21,713,029
-------------------------------------------------------------------------------------
                Computer Storage & Peripherals -- 6.2%
     679,124    Apple, Inc.                                            $   74,961,710
     997,080    EMC Corp.                                                  29,653,159
                                                                       --------------
                                                                       $  104,614,869
                                                                       --------------
                Total Technology Hardware & Equipment                  $  126,327,898
-------------------------------------------------------------------------------------
                SEMICONDUCTORS & SEMICONDUCTOR EQUIPMENT -- 1.7%
                Semiconductors -- 1.7%
     174,968    Analog Devices, Inc.                                   $    9,714,223
     416,528    Xilinx, Inc.                                               18,031,497
                                                                       --------------
                                                                       $   27,745,720
                                                                       --------------
                Total Semiconductors & Semiconductor Equipment         $   27,745,720
-------------------------------------------------------------------------------------
                TELECOMMUNICATION SERVICES -- 2.0%
                Integrated Telecommunication Services -- 2.0%
     720,778    Verizon Communications, Inc.                           $   33,717,995
                                                                       --------------
                Total Telecommunication Services                       $   33,717,995
-------------------------------------------------------------------------------------
                UTILITIES -- 3.1%
                Electric Utilities -- 3.1%
     412,851    American Electric Power Co., Inc.                      $   25,068,313
     261,544    NextEra Energy, Inc.*                                      27,799,512
                                                                       --------------
                                                                       $   52,867,825
                                                                       --------------
                Total Utilities                                        $   52,867,825
-------------------------------------------------------------------------------------
                TOTAL COMMON STOCKS
                (Cost $1,338,713,485)                                  $1,674,661,222
-------------------------------------------------------------------------------------
                TOTAL INVESTMENT IN SECURITIES -- 99.4%
                (Cost $1,338,713,485) (a)                              $1,674,661,222
-------------------------------------------------------------------------------------
                OTHER ASSETS & LIABILITIES -- 0.6%                     $   10,911,684
-------------------------------------------------------------------------------------
                TOTAL NET ASSETS -- 100.0%                             $1,685,572,906
=====================================================================================


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

20 Pioneer Core Equity Fund | Annual Report | 12/31/14


*          Non-income producing security.

(A.D.R.)   American Depositary Receipts.

REIT       Real Estate Investment Trust.

(a)        At December 31, 2014, the net unrealized appreciation on investments
           based on cost for federal income tax purposes of $1,342,656,344 was
           as follows:



                                                                                  
             Aggregate gross unrealized appreciation for all investments in which
                there is an excess of value over tax cost                            $342,970,662

             Aggregate gross unrealized depreciation for all investments in which
                there is an excess of tax cost over value                             (10,965,784)
                                                                                     ------------
             Net unrealized appreciation                                             $332,004,878
                                                                                     ============


Purchases and sales of securities (excluding temporary cash investments) for the
year ended December 31, 2014 aggregated $935,234,019 and $1,061,245,415,
respectively.

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

     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.) See Notes to Financial Statements -- Note 1A.

     Level 3 - significant unobservable inputs (including the Fund's own
               assumptions in determining fair value of investments) See Notes
               to Financial Statements -- Note 1A.

Generally, equity securities are categorized as Level 1, fixed income securities
and senior loans as Level 2 and securities valued using fair value methods
(other than prices supplied by independent pricing services or broker-dealers)
as Level 3.

The following is a summary of the inputs used as of December 31, 2014, in
valuing the Fund's investments:



--------------------------------------------------------------------------------
                       Level 1            Level 2      Level 3    Total
--------------------------------------------------------------------------------
                                                      
Common Stocks          $1,674,661,222     $ --         $ --       $1,674,661,222
--------------------------------------------------------------------------------
   Total               $1,674,661,222     $ --         $ --       $1,674,661,222
================================================================================


During the year ended December 31, 2014, there were no transfers between Levels
1, 2 and 3.

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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 21


Statement of Assets and Liabilities | 12/31/14



                                                               
ASSETS:
  Investment in securities (cost $1,338,713,485)                  $1,674,661,222
  Cash                                                                10,754,844
  Receivables --
     Fund shares sold                                                    123,281
     Dividends                                                         1,870,582
---------------------------------------------------------------------------------
        Total assets                                              $1,687,409,929
=================================================================================
LIABILITIES:
  Payables --
     Fund shares repurchased                                      $    1,255,996
     Dividends                                                            67,845
  Due to affiliates                                                      319,054
  Accrued expenses                                                       194,128
---------------------------------------------------------------------------------
        Total liabilities                                         $    1,837,023
=================================================================================
NET ASSETS:
  Paid-in capital                                                 $1,624,444,097
  Undistributed net investment income                                  1,201,447
  Accumulated net realized loss on investments                      (276,020,375)
  Net unrealized appreciation on investments                         335,947,737
---------------------------------------------------------------------------------
        Total net assets                                          $1,685,572,906
=================================================================================
NET ASSET VALUE PER SHARE:
(No par value, unlimited number of shares authorized)
  Class A (based on $1,605,301,457/93,413,351 shares)             $        17.18
  Class C (based on $13,847,805/894,546 shares)                   $        15.48
  Class Y (based on $66,423,644/3,830,547 shares)                 $        17.34
MAXIMUM OFFERING PRICE:
  Class A ($17.18/94.25%)                                         $        18.23
=================================================================================


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

22 Pioneer Core Equity Fund | Annual Report | 12/31/14


Statement of Operations

For the Year Ended 12/31/14



                                                                         
INVESTMENT INCOME:
  Dividends                                                    $  32,258,975
  Interest                                                             2,731
  Miscellaneous                                                      250,169
--------------------------------------------------------------------------------------------
         Total investment income                                               $ 32,511,875
--------------------------------------------------------------------------------------------
EXPENSES:
  Management fees                                              $   8,240,395
  Transfer agent fees
     Class A                                                       1,150,460
     Class B*                                                         17,098
     Class C                                                          16,517
     Class Y                                                           1,160
  Distribution fees
     Class A                                                       3,947,999
     Class B*                                                         21,921
     Class C                                                         117,175
  Shareholder communications expense                               1,053,913
  Administrative reimbursements                                      493,727
  Custodian fees                                                      27,954
  Registration fees                                                   77,169
  Professional fees                                                  138,036
  Printing expense                                                    43,084
  Fees and expenses of nonaffiliated Trustees                         54,706
  Miscellaneous                                                       56,002
--------------------------------------------------------------------------------------------
     Total operating expenses                                                  $ 15,457,316
     Less fees waived and expenses reimbursed by
         Pioneer Investment Management, Inc.                                        (11,597)
--------------------------------------------------------------------------------------------
     Net operating expenses                                                    $ 15,445,719
--------------------------------------------------------------------------------------------
         Interest expense                                                      $      2,285
--------------------------------------------------------------------------------------------
     Total operating expenses and interest expense                             $ 15,448,004
--------------------------------------------------------------------------------------------
         Net investment income                                                 $ 17,063,871
--------------------------------------------------------------------------------------------
REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS
AND FOREIGN CURRENCY TRANSACTIONS
  Net realized gain (loss) on:
     Investments                                               $ 110,426,038
     Other assets and liabilities denominated in
         foreign currencies                                               (4)  $110,426,034
--------------------------------------------------------------------------------------------
  Change in net unrealized appreciation (depreciation) on:
     Investments                                               $  36,075,800
     Other assets and liabilities denominated in
         foreign currencies                                              (16)  $ 36,075,784
--------------------------------------------------------------------------------------------
  Net gain on investments and foreign currency transactions                    $146,501,818
--------------------------------------------------------------------------------------------
  Net increase in net assets resulting from operations                         $163,565,689
============================================================================================


* Class B shares converted to Class A shares on November 10, 2014.

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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 23


Statements of Changes in Net Assets



--------------------------------------------------------------------------------------------
                                                            Year Ended       Year Ended
                                                            12/31/14         12/31/13
--------------------------------------------------------------------------------------------
                                                                       
FROM OPERATIONS:
Net investment income                                       $   17,063,871   $    6,309,230
Net realized gain on investments and foreign
  currency transactions                                        110,426,034      251,084,688
Change in net unrealized appreciation (depreciation) on
  investments and foreign currency transactions                 36,075,784      (42,801,664)
--------------------------------------------------------------------------------------------
      Net increase in net assets resulting
          from operations                                   $  163,565,689   $  214,592,254
--------------------------------------------------------------------------------------------
DISTRIBUTIONS TO SHAREOWNERS:
Net investment income:
      Class A ($0.16 and $0.09* per share, respectively)    $  (15,012,625)  $   (5,422,071)
      Class C ($0.06 and $0.00* per share, respectively)           (55,064)              --
      Class Y ($0.22 and $0.14* per share, respectively)          (824,165)        (462,355)
--------------------------------------------------------------------------------------------
         Total distributions to shareowners                 $  (15,891,854)  $   (5,884,426)
--------------------------------------------------------------------------------------------
FROM FUND SHARE TRANSACTIONS:
Net proceeds from sale or exchange of shares                $   53,337,764   $   40,425,981
Shares issued in reorganization                                         --    1,456,910,518
Reinvestment of distributions                                   14,517,279        5,188,297
Cost of shares repurchased                                    (189,173,394)    (114,662,950)
--------------------------------------------------------------------------------------------
      Net increase (decrease) in net assets resulting from
         Fund share transactions                            $ (121,318,351)  $1,387,861,846
--------------------------------------------------------------------------------------------
      Net increase in net assets                            $   26,355,484   $1,596,569,674
NET ASSETS:
Beginning of year                                           $1,659,217,422   $   62,647,748
--------------------------------------------------------------------------------------------
End of year                                                 $1,685,572,906   $1,659,217,422
============================================================================================
Undistributed net investment income                         $    1,201,447   $      232,572
============================================================================================


*   Historical per share amounts prior to June 7, 2013 have been adjusted to
    reflect the conversion ratios used for the reorganization of the fund with
    Pioneer Research Fund.

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

24 Pioneer Core Equity Fund | Annual Report | 12/31/14




------------------------------------------------------------------------------------------------
                                '14 Shares      '14 Amount        '13 Shares     '13 Amount
------------------------------------------------------------------------------------------------
                                                                     
Class A*
Shares sold                       1,659,757     $   27,166,910      1,531,805    $   21,575,373
Shares issued
   in reorganization                     --                 --    104,128,727     1,440,920,816
Reinvestment of
   distributions                    817,018         14,256,940        324,881         5,078,946
Less shares repurchased         (10,011,567)      (163,425,287)    (7,019,110)     (101,470,474)
------------------------------------------------------------------------------------------------
       Net increase
           (decrease)            (7,534,792)    $ (122,001,437)    98,966,303    $1,366,104,661
================================================================================================
Class B* (a)
Shares sold or exchanged              5,021     $       72,059         11,081    $      136,434
Shares issued
   in reorganization                     --                 --        179,044         2,266,334
Reinvestment of
   distributions                         --                 --             --                --
Less shares repurchased            (214,474)        (3,255,376)       (86,727)       (1,090,017)
------------------------------------------------------------------------------------------------
       Net increase
           (decrease)              (209,453)    $   (3,183,317)       103,398    $    1,312,751
================================================================================================
Class C*
Shares sold                         300,009     $    4,477,066        181,450    $    2,280,382
Shares issued
   in reorganization                     --                 --        388,889         4,870,847
Reinvestment of
   distributions                      3,064             48,167             --               206
Less shares repurchased            (191,359)        (2,797,736)      (125,491)       (1,610,723)
------------------------------------------------------------------------------------------------
       Net increase                 111,714     $    1,727,497        444,848    $    5,540,712
================================================================================================
Class Y*
Shares sold                       1,260,451     $   21,621,729      1,095,403    $   16,433,792
Shares issued
   in reorganization                     --                 --        634,124         8,852,521
Reinvestment of
   distributions                     12,055            212,172          7,172           109,145
Less shares repurchased          (1,216,700)       (19,694,995)      (745,827)      (10,491,736)
------------------------------------------------------------------------------------------------
       Net increase                  55,806     $    2,138,906        990,872    $   14,903,722
================================================================================================


*   Historical per share amounts prior to June 7, 2013 have been adjusted to
    reflect the conversion ratios used for the reorganization of the fund with
    Pioneer Research Fund.

(a) Class B shares converted to Class A shares on November 10, 2014.

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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 25


Financial Highlights



---------------------------------------------------------------------------------------------------------------------------------
                                                               Year          Year          Year         Year          Year
                                                               Ended         Ended         Ended        Ended         Ended
                                                               12/31/14      12/31/13(a)   12/31/12(a)  12/31/11(a)   12/31/10(a)
---------------------------------------------------------------------------------------------------------------------------------
                                                                                                       
Class A
Net asset value, beginning of period                           $    15.70    $    12.06    $ 10.61      $ 10.57       $  9.19
---------------------------------------------------------------------------------------------------------------------------------
Increase (decrease) from investment operations:
   Net investment income (loss)                                $     0.18    $     0.10    $  0.08      $  0.06       $  0.06
   Net realized and unrealized gain (loss) on investments            1.46          3.63       1.45         0.05          1.38
---------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) from investment operations             $     1.64    $     3.73    $  1.53      $  0.11       $  1.44
---------------------------------------------------------------------------------------------------------------------------------
Distribution to shareowners:
   Net investment income                                       $    (0.16)   $    (0.09)   $ (0.08)     $ (0.07)      $ (0.06)
---------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net asset value                     $     1.48    $     3.64    $  1.45      $  0.04       $  1.38
---------------------------------------------------------------------------------------------------------------------------------
Net asset value, end of period                                 $    17.18    $    15.70    $ 12.06      $ 10.61       $ 10.57
=================================================================================================================================
Total return*                                                       10.44%        31.02%     14.51%        0.97%        15.58%
Ratio of total expenses plus interest expense
   to average net assets (b)                                         0.94%         0.99%      1.25%        1.25%         1.25%
Ratio of net investment income (loss) to average net assets          1.03%         0.70%      0.76%        0.59%         0.56%
Portfolio turnover rate                                                57%           67%        59%          57%           57%
Net assets, end of period (in thousands)                       $1,605,301    $1,585,294    $23,907      $15,957       $13,890
Ratios with no waiver of fees and assumption of expenses by
   the Adviser and no reduction for fees paid indirectly:
   Total expenses plus interest expense (b)                          0.94%         0.99%      1.59%        1.55%         1.53%
   Net investment income (loss)                                      1.03%         0.70%      0.42%        0.29%         0.28%
=================================================================================================================================


*    Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions, the complete redemption of the
     investment at net asset value at the end of each period and no sales
     charges. Total return would be reduced if sales charges were taken into
     account.

(a)  The Fund acquired the assets and liabilities of Pioneer Research Fund (the
     "predecessor fund") on June 7, 2013 (the "reorganization"). As a result of
     the reorganization, the predecessor fund's performance and financial
     history became the performance and financial history of the Fund.
     Historical per-share amounts prior to June 7, 2013 have been adjusted to
     reflect the conversion ratio used to align the net asset values of the
     Predecessor Fund with those of the Fund.

(b)  Includes interest expense of 0.00%+, 0.00%, 0.00%, 0.00% and 0.00%,
     respectively.

+    Amount rounds to less than 0.01%.

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

26 Pioneer Core Equity Fund | Annual Report | 12/31/14




---------------------------------------------------------------------------------------------------------------------------------
                                                               Year          Year          Year         Year          Year
                                                               Ended         Ended         Ended        Ended         Ended
                                                               12/31/14      12/31/13(a)   12/31/12(a)  12/31/11(a)   12/31/10(a)
---------------------------------------------------------------------------------------------------------------------------------
                                                                                                       
Class C
Net asset value, beginning of period                           $ 14.19       $  10.93      $  9.65      $   9.64      $   8.42
---------------------------------------------------------------------------------------------------------------------------------
Increase (decrease) from investment operations:
   Net investment income (loss)                                $  0.02       $  (0.02)(b)  $ (0.01)(b)  $  (0.03)     $  (0.03)
   Net realized and unrealized gain (loss) on investments         1.33           3.28         1.30          0.04          1.25
---------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) from investment operations             $  1.35       $   3.26      $  1.29      $   0.01      $   1.22
---------------------------------------------------------------------------------------------------------------------------------
Distribution to shareowners:
   Net investment income                                       $ (0.06)      $     --      $ (0.01)     $     --      $     --
---------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net asset value                     $  1.29       $   3.26      $  1.28      $   0.01      $   1.22
---------------------------------------------------------------------------------------------------------------------------------
Net asset value, end of period                                 $ 15.48       $  14.19      $ 10.93      $   9.65      $   9.64
=================================================================================================================================
Total return*                                                     9.52%         29.81%       13.37%         0.11%        14.52%
Ratio of total expenses plus interest expense
   to average net assets (c)                                      1.81%          1.92%        2.15%         2.15%         2.15%
Ratio of net investment income (loss) to average net assets       0.14%         (0.17)%      (0.14)%       (0.32)%       (0.33)%
Portfolio turnover rate                                             57%            67%          59%           57%           57%
Net assets, end of period (in thousands)                       $13,848       $ 11,112      $ 3,695      $  1,829      $  1,630
Ratios with no waiver of fees and assumption of expenses by
   the Adviser and no reduction for fees paid indirectly:
   Total expenses plus interest expense (c)                       1.81%          1.92%        2.31%         2.35%         2.38%
   Net investment income (loss)                                   0.14%         (0.17)%      (0.30)%       (0.52)%       (0.56)%
=================================================================================================================================



*    Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions, the complete redemption of the
     investment at net asset value at the end of each period and no sales
     charges. Total return would be reduced if sales charges were taken into
     account.

(a)  The Fund acquired the assets and liabilities of Pioneer Research Fund (the
     "predecessor fund") on June 7, 2013 (the "reorganization"). As a result of
     the reorganization, the predecessor fund's performance and financial
     history became the performance and financial history of the Fund.
     Historical per-share amounts prior to June 7, 2013 have been adjusted to
     reflect the conversion ratio used to align the net asset values of the
     Predecessor Fund with those of the Fund.

(b)  The amount shown for a share outstanding does not correspond with the net
     investment gain on the Statement of Operations for the period due to timing
     of the sales and repurchases of shares.


(c)  Includes interest expense of 0.00%+, 0.00%, 0.00%, 0.00% and 0.00%,
     respectively.

+    Amount rounds to less than 0.01%.

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

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 27


Financial Highlights (continued)



---------------------------------------------------------------------------------------------------------------------------------
                                                               Year          Year          Year         Year          Year
                                                               Ended         Ended         Ended        Ended         Ended
                                                               12/31/14      12/31/13(a)   12/31/12(a)  12/31/11(a)   12/31/10(a)
---------------------------------------------------------------------------------------------------------------------------------
                                                                                                       
Class Y
Net asset value, beginning of period                           $ 15.85       $ 12.17       $ 10.69      $ 10.66       $  9.27
---------------------------------------------------------------------------------------------------------------------------------
Increase (decrease) from investment operations:
   Net investment income (loss)                                $  0.20       $  0.14       $  0.11      $  0.10       $  0.09
   Net realized and unrealized gain (loss) on investments         1.51          3.68          1.47         0.03          1.39
---------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) from investment operations             $  1.71       $  3.82       $  1.58      $  0.13       $  1.48
---------------------------------------------------------------------------------------------------------------------------------
Distribution to shareowners:
   Net investment income                                       $ (0.22)      $ (0.14)      $ (0.10)     $ (0.10)      $ (0.09)
---------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net asset value                     $  1.49       $  3.68       $  1.48      $  0.03       $  1.39
---------------------------------------------------------------------------------------------------------------------------------
Net asset value, end of period                                 $ 17.34       $ 15.85       $ 12.17      $ 10.69       $ 10.66
=================================================================================================================================
Total return*                                                    10.75%        31.49%        14.81%        1.20%        15.89%
Ratio of total expenses plus interest expense
   to average net assets (b)                                      0.63%         0.75%         1.02%        0.97%         0.96%
Ratio of net investment income (loss) to average net assets       1.37%         1.01%         0.97%        0.81%         0.86%
Portfolio turnover rate                                             57%           67%           59%          57%           57%
Net assets, end of period (in thousands)                       $66,424       $59,812       $33,875      $30,811       $47,810
=================================================================================================================================


*    Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions, the complete redemption of the
     investment at net asset value at the end of each period and no sales
     charges. Total return would be reduced if sales charges were taken into
     account.

(a)  The Fund acquired the assets and liabilities of Pioneer Research Fund (the
     "predecessor fund") on June 7, 2013 (the "reorganization"). As a result of
     the reorganization, the predecessor fund's performance and financial
     history became the performance and financial history of the Fund.
     Historical per-share amounts prior to June 7, 2013 have been adjusted to
     reflect the conversion ratio used to align the net asset values of the
     Predecessor Fund with those of the Fund.

(b)  Includes interest expense of 0.00%+, 0.00%, 0.00%, 0.00% and 0.00%,
     respectively.

+    Amount rounds to less than 0.01%.

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

28 Pioneer Core Equity Fund | Annual Report | 12/31/14

Notes to Financial Statements | 12/31/14

1. Organization and Significant Accounting Policies

Pioneer Core Equity Fund (the Fund) is a diversified series of Pioneer Series
Trust XI, a Delaware statutory trust registered under the Investment Company Act
of 1940 as an open-end management investment company. The Fund acquired the
assets and liabilities of Pioneer Research Fund on June 7, 2013. Pioneer
Research Fund was the accounting survivor of the reorganization. Accordingly,
Pioneer Research Fund's performance and financial history became the performance
and financial history of the Fund. The financial highlights and shareholder
activity, as reflected in the statement of changes in net assets, have been
adjusted to reflect the conversion ratios used for the reorganization of the
Fund with Pioneer Research Fund. Prior to the reorganization, the Fund was named
Pioneer Value Fund. The investment objective of the Fund is to seek long-term
capital growth.

The Fund offers three classes of shares designated as Class A, Class C and Class
Y shares. The Fund ceased to offer Class B shares on November 10, 2014. Class B
shares were converted to Class A shares as of the close of business on November
10, 2014. Each class of shares represents an interest in the same portfolio of
investments of the Fund and has identical rights (based on relative net asset
values) to assets and liquidation proceeds. Share classes can bear different
rates of class-specific fees and expenses such as transfer agent and
distribution fees. Differences in class-specific fees and expenses will result
in differences in net investment income and, therefore, the payment of different
dividends from net investment income earned by each class. The Amended and
Restated Declaration of Trust of the Fund gives the Board the flexibility to
specify either per-share voting or dollar-weighted voting when submitting
matters for shareholder approval. Under per-share voting, each share of a class
of the Fund is entitled to one vote. Under dollar-weighted voting, a
shareholder's voting power is determined not by the number of shares owned, but
by the dollar value of the shares on the record date. Each share class has
exclusive voting rights with respect to matters affecting only that class,
including with respect to the distribution plan for that class. There is no
distribution plan for Class Y shares.

The Fund's financial statements have been prepared in conformity with U.S.
generally accepted accounting principles that require the management of the Fund
to, among other things, make estimates and assumptions that affect the reported
amounts of assets and liabilities, the disclosure of contingent assets and
liabilities at the date of the financial statements, and the reported amounts of
income, expenses and gain or loss on investments during the reporting period.
Actual results could differ from those estimates.

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 29


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

A.   Security Valuation

     Security transactions are recorded as of trade date. The net asset value of
     the Fund is computed once daily, on each day the New York Stock Exchange
     (NYSE) is open, as of the close of regular trading on the NYSE. In
     computing the net asset value, securities that have traded on an exchange
     are valued at the last sale price on the principal exchange where they are
     traded. Securities that have not traded on the date of valuation, or
     securities for which sale prices are not available, generally are valued at
     the mean between the last bid and asked prices. Shares of money market
     mutual funds are valued at such funds' net asset value. Cash may include
     overnight time deposits at approved financial institutions.

     Trading in foreign securities is substantially completed each day at
     various times prior to the close of the NYSE. The values of such securities
     used in computing the net asset value of the Fund's shares are determined
     as of such times.

     Securities for which independent pricing services are unable to supply
     prices or for which market prices and/or quotations are not readily
     available or are considered to be unreliable are valued by a fair valuation
     team comprised of certain personnel of Pioneer Investment Management, Inc.
     (PIM), the Fund's investment adviser, pursuant to procedures adopted by the
     Fund's Board of Trustees. PIM's fair valuation team uses fair value methods
     approved by the Valuation Committee of the Board of Trustees. PIM's fair
     valuation team is responsible for monitoring developments that may impact
     fair valued securities and for discussing and assessing fair values on an
     ongoing basis, and at least quarterly, with the Valuation Committee of the
     Board of Trustees.

     Inputs used when applying fair value methods to value a security may
     include credit ratings, the financial condition of the company, current
     market conditions and comparable securities. The Fund may use fair value
     methods if it is determined that a significant event has occurred after the
     close of the exchange or market on which the security trades and prior to
     the determination of the Fund's net asset value. Examples of a significant
     event might include political or economic news, corporate restructurings,
     natural disasters, terrorist activity or trading halts. Thus, the valuation
     of the Fund's securities may differ significantly from exchange prices and
     such differences could be material.

     At December 31, 2014, there were no securities that were valued using fair
     value methods (other than securities that were valued using prices supplied
     by independent pricing services or broker-dealers).

30 Pioneer Core Equity Fund | Annual Report | 12/31/14


B.   Investment Income and Transactions

     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 Fund becomes aware of the ex-dividend
     data in the exercise of reasonable diligence.

     Interest income, including interest on income bearing cash accounts, is
     recorded on the accrual basis. Dividend and interest income are reported
     net of unrecoverable foreign taxes withheld at the applicable country
     rates.

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

C.   Foreign Currency Translation

     The books and records of the Fund are maintained in U.S. dollars. Amounts
     denominated in foreign currencies are translated into U.S. dollars using
     current exchange rates.

     Net realized gains and losses on foreign currency transactions, if any,
     represent, among other things, the net realized gains and losses on foreign
     currency contracts, disposition of foreign currencies and the difference
     between the amount of income accrued and the U.S. dollars actually
     received. Further, the effects of changes in foreign currency exchange
     rates on investments are not segregated in the statement of operations from
     the effects of changes in the market prices of those securities, but are
     included with the net realized and unrealized gain or loss on investments.

D.   Forward Foreign Currency Contracts

     The Fund may enter into forward foreign currency contracts (contracts) for
     the purchase or sale of a specific foreign currency at a fixed price on a
     future date. All contracts are marked to market daily at the applicable
     exchange rates, and any resulting unrealized appreciation or depreciation
     are recorded in the Fund's financial statements. The Fund records realized
     gains and losses at the time a contract is offset by entry into a closing
     transaction or extinguished by delivery of the currency. Risks may arise
     upon entering into these contracts from the potential inability of
     counterparties to meet the terms of the contract and from unanticipated
     movements in the value of foreign currencies relative to the U.S. dollar.
     The Fund had no outstanding forward foreign currency contracts as of
     December 31, 2014.

E.   Federal Income Taxes

     It is the Fund'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 provision for federal income taxes is required.
     As

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 31


     of December 31, 2014, the Fund did not accrue any interest or penalties
     with respect to uncertain tax positions, which, if applicable, would be
     recorded as an income tax expense in the Statement of Operations. Tax
     returns filed within the prior three years remain subject to examination by
     Federal and State tax authorities.

     The amount and character of income and capital gain distributions to
     shareowners are determined in accordance with federal income tax rules,
     which may differ from U.S. generally accepted accounting principles.
     Distributions in excess of net investment income or net realized gains are
     temporary overdistributions for financial statement purposes resulting from
     differences in the recognition or classification of income or distributions
     for financial statement and tax purposes. Capital accounts within the
     financial statements are adjusted for permanent book/tax differences to
     reflect tax character, but are not adjusted for temporary differences. At
     December 31, 2014, the Fund reclassified $221,544 to decrease paid in
     capital, $203,142 to decrease undistributed net investment income and
     $424,686 to decrease accumulated net realized loss on investments to
     reflect permanent book/tax differences. These adjustments have no impact on
     net assets or the results of operations.

     At December 31, 2014, the Fund had a net capital loss carryforward of
     $270,876,069, which will expire in 2017, if not utilized.

     During the year ended December 31, 2014, a capital loss carryforward of
     $112,048,086 was utilized to offset net realized gains by the Fund.

     The tax character of distributions paid during the years ended December 31,
     2014 and December 31, 2013 were as follows:



     ---------------------------------------------------------------------------
                                                            2014            2013
     ---------------------------------------------------------------------------
                                                                
     Distributions paid from:
     Ordinary income                                 $15,891,854      $5,884,426
     ---------------------------------------------------------------------------
          Total                                      $15,891,854      $5,884,426
     ===========================================================================


The following shows components of distributable earnings on a federal income tax
basis at December 31, 2014:



     ---------------------------------------------------------------------------
                                                                            2014
     ---------------------------------------------------------------------------
                                                                
     Distributable earnings:
     Capital loss carryforward                                     $(270,876,069)
     Net unrealized appreciation                                     332,004,878
     ---------------------------------------------------------------------------
          Total                                                    $  61,128,809
     ===========================================================================


32 Pioneer Core Equity Fund | Annual Report | 12/31/14


     The difference between book-basis and tax-basis net unrealized appreciation
     is attributable to the tax deferral of losses on wash sales, tax basis
     adjustments on Real Estate Investment Trust (REIT) holdings, partnerships
     and other holdings.

F.   Fund Shares

     The Fund records sales and repurchases of its shares as of trade date.
     Pioneer Funds Distributor, Inc. (PFD), the principal underwriter for the
     Fund and a wholly owned indirect subsidiary of UniCredit S.p.A.
     (UniCredit), earned $59,124 in underwriting commissions on the sale of
     Class A shares during the year ended December 31, 2014.

G.   Class Allocations

     Income, common expenses and realized and unrealized gains and losses are
     calculated at the Fund level and allocated daily to each class of shares
     based on its respective percentage of adjusted net assets at the beginning
     of the day.

     Distribution fees are calculated based on the average daily net asset value
     attributable to Class A and Class C shares of the Fund, respectively (see
     Note 4). Class Y shares do not pay distribution fees. All expenses and fees
     paid to the transfer agent, Pioneer Investment Management Shareholder
     Services, Inc. (PIMSS), for its services are allocated among the classes of
     shares based on the number of accounts in each class and the ratable
     allocation of related out-of-pocket expenses (see Note 3).

     Distributions to shareowners are recorded as of the ex-dividend date.
     Distributions paid by the Fund with respect to each class of shares are
     calculated in the same manner and at the same time, except that net
     investment income dividends to Class A, Class C and Class Y shares can
     reflect different transfer agent and distribution expense rates.

H.   Risks

     At times, the Fund's investments may represent industries or industry
     sectors that are interrelated or have common risks, making the Fund more
     susceptible to any economic, political, or regulatory developments or other
     risks affecting those industries and sectors. The Fund's prospectus
     contains unaudited information regarding the Fund's principal risks. Please
     refer to that document when considering the Fund's principal risks.

I.   Repurchase Agreements

     With respect to repurchase agreements entered into by the Fund, the value
     of the underlying securities (collateral), including accrued interest, is
     required to be equal to or in excess of the repurchase price. The
     collateral for all repurchase agreements is held in safekeeping in the
     customer-only account of

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 33


     the Fund's custodian or a subcustodian of the Fund. PIM is responsible for
     determining that the value of the collateral remains at least equal to the
     repurchase price. At December 31, 2014, the Fund had no open repurchase
     agreements.

2. Management Agreement

PIM, a wholly owned indirect subsidiary of UniCredit, manages the Fund's
portfolio. Management fees are calculated daily at the annual rate of 0.50% of
the Fund's average daily net assets. Prior to June 7, 2013, the Fund paid a
basic management fee that was calculated at the annual rate of 0.60% of the
Fund's average daily net assets up to $5 billion, 0.575% of the next $5 billion
and 0.55% on the excess over $10 billion. The basic fee increased or decreased
by a maximum of 0.10%, based on the investment performance of the Fund's Class A
shares as compared to the Russell 1000 Value Index. The performance comparison
was made for a rolling 36-month period. Prior to June 7, 2013, the Pioneer
Research Fund (the accounting survivor of the reorganization) paid a management
fee that was calculated daily at the annual rate of 0.65% of such fund's average
daily net assets up to $1 billion, 0.60% of the next $4 billion and 0.55% on
assets over $5 billion. For the year ended December 31, 2014, the net management
fee (excluding waivers and/or assumption of expenses) was equivalent to 0.50% of
the Fund's average daily net assets.

PIM has contractually agreed to limit ordinary operating expenses of the Fund to
the extent required to reduce Fund expenses to 1.25% and 2.15% of the average
daily net assets attributable to Class A and Class C shares, respectively. Class
Y shares do not have an expense limitation. Fees waived and expenses reimbursed
during the year ended December 31, 2014 are reflected on the Statement of
Operations. These expense limitations are in effect through May 1, 2015. There
can be no assurance that PIM will extend the expense limitation agreement for a
class of shares beyond the date referred to above.

In addition, under the management and administration agreements, certain other
services and costs, including accounting, regulatory reporting and insurance
premiums, are paid by the Fund as administrative reimbursements. Included in
"Due to affiliates" reflected on the Statement of Assets and Liabilities is
$48,565 in management fees, administrative costs and certain other
reimbursements payable to PIM at December 31, 2014.

3. Transfer Agent

PIMSS, a wholly owned indirect subsidiary of UniCredit, provides substantially
all transfer agent and shareowner services to the Fund at negotiated rates.

In addition, the Fund reimburses PIMSS for out-of-pocket expenses incurred by
PIMSS related to shareholder communications activities such as proxy and
statement mailings, outgoing phone calls and omnibus relationship contracts.

34 Pioneer Core Equity Fund | Annual Report | 12/31/14


For the year ended December 31, 2014, such out-of-pocket expenses by class of
shares were as follows:



--------------------------------------------------------------------------------
Shareholder Communications:
--------------------------------------------------------------------------------
                                                                   
Class A                                                               $  991,768
Class B                                                                    7,640
Class C                                                                   13,439
Class Y                                                                   41,066
--------------------------------------------------------------------------------
  Total                                                               $1,053,913
================================================================================


Included in "Due to affiliates" reflected on the Statement of Assets and
Liabilities is $247,530 in transfer agent fees and out-of-pocket reimbursements
payable to PIMSS at December 31, 2014.

4. Distribution Plan

The Fund has adopted a Distribution Plan pursuant to Rule 12b-1 of the
Investment Company Act of 1940 with respect to its Class A and Class C shares.
Pursuant to the Plan, the Fund pays PFD 0.25% of the average daily net assets
attributable to Class A shares as compensation for personal services and/or
account maintenance services or distribution services with regard to Class A
shares. Pursuant to the Plan, the Fund also pays PFD 1.00% of the average daily
net assets attributable to Class C shares. The fee for Class C shares consists
of a 0.25% service fee and a 0.75% distribution fee paid as compensation for
personal services and/or account maintenance services or distribution services
with regard to Class C shares. Included in "Due to affiliates" reflected on the
Statement of Assets and Liabilities is $22,959 in distribution fees payable to
PFD at December 31, 2014.

In addition, redemptions of each class of shares (except Class Y shares) may be
subject to a contingent deferred sales charge (CDSC). A CDSC of 1.00% may be
imposed on redemptions of certain net asset value purchases of Class A shares
within 12 months of purchase. Redemptions of Class C shares within 12 months of
purchase are subject to a CDSC of 1.00%, based on the lower of cost or market
value of shares being redeemed. Shares purchased as part of an exchange remain
subject to any CDSC that applied to the original purchase of those shares. There
is no CDSC for Class Y shares. Proceeds from the CDSC are paid to PFD. For the
year ended December 31, 2014, CDSC in the amount of $1,134 were paid to PFD.

5. Expense Offset Arrangements

The Fund has entered into certain expense offset arrangements with PIMSS which
may result in a reduction in the Fund's total expenses due to interest earned on
cash held by PIMSS. For the year ended December 31, 2014, the Fund's expenses
were not reduced under such arrangements.

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 35


6. Reorganization Information

On June 7, 2013 ("Closing Date"), Pioneer Research Fund (the "predecessor fund")
was reorganized with the Fund. The purpose of this transaction was to combine
two funds (managed by PIM) with similar investment objectives and strategies.

This tax-free reorganization was accomplished by exchanging the assets and
liabilities of the predecessor fund for shares of the Fund. Shareowners holding
Class A, Class B*, Class C and Class Y of the predecessor fund received Class A,
Class B, Class C and Class Y shares of the Fund, respectively, in the
reorganization. The investment portfolio of the predecessor fund, with an
aggregate value of $69,338,811 and an identified cost of $51,739,180 at June 7,
2013, was the principal asset acquired by the Fund.

For financial reporting purposes, assets received and shares issued by the Fund
were recorded at net asset value, however, the cost basis of the investments
received from the predecessor fund was carried forward to align ongoing
reporting of the Fund's realized and unrealized gains and losses with amounts
distributable to shareowners for tax reporting purposes.

The Fund was the legal survivor of the reorganization. The predecessor fund was
the accounting survivor of the reorganization. Accordingly, the predecessor
fund's performance and financial history became the performance and financial
history of the Fund. Prior to the reorganization, the Fund was named Pioneer
Value Fund.

The following charts shows the details of the reorganization as of the Closing
Date:



---------------------------------------------------------------------------------------------
                                                  Pioneer                Pioneer Core
                        Pioneer Value Fund        Research Fund          Equity Fund
                        (Pre-Reorganization)      (Pre-Reorganization)   (Post-Reorganization)
---------------------------------------------------------------------------------------------
                                                                
Net Assets
Class A                 $ 1,440,920,816           $ 28,058,361           $ 1,468,979,177
Class B                       2,266,334                864,098                 3,130,432
Class C                       4,870,847              4,859,909                 9,730,756
Class Y                       8,852,521             35,435,343                44,287,864
---------------------------------------------------------------------------------------------
Total Net Assets        $ 1,456,910,518           $ 69,217,711           $ 1,526,128,229
---------------------------------------------------------------------------------------------
Shares Outstanding
Class A                    104,128,727               2,027,338*              106,156,065
Class B                        179,044                  68,254*                  247,298
Class C                        388,889                 387,861*                  776,750
Class Y                        634,124               2,538,345*                3,172,469


*    Class B shares of the Fund converted to Class A shares on November 10.
     2014. (See Note 9).

36 Pioneer Core Equity Fund | Annual Report | 12/31/14




---------------------------------------------------------------------------------------------
                        Pre-conversion             Conversion            Post-conversion
                        shares                     Ratio*                shares
---------------------------------------------------------------------------------------------
                                                                      

Class A                        2,270,553                 0.8929                2,027,338
Class B                           74,320                 0.9184                   68,254
Class C                          415,977                 0.9324                  387,861
Class Y                        2,841,872                 0.8932                2,538,345


*    Share amounts have been adjusted to reflect the conversion ratios utilized
     to align the net asset values of the Predecessor Fund with those of the
     Fund.



---------------------------------------------------------------------------------------------
                                                                         Shares issued
                                                   Exchange Ratio        in reorganization**
---------------------------------------------------------------------------------------------
                                                                       
Class A                                                    1.000             104,128,727
Class B                                                    1.000                 179,044
Class C                                                    1.000                 388,889
Class Y                                                    1.000                 634,124


**   Reflects shares issued by the predecessor fund, the accounting survivor, as
     shown on the Statement of Changes. Unrealized Accumulated



---------------------------------------------------------------------------------------------
                                                   Unrealized            Accumulated
                                                   Appreciation          Gain (Loss) on
                                                   on Closing Date       Closing Date
---------------------------------------------------------------------------------------------
                                                                   
Fund                                               $331,284,140          $(610,173,465)
Predecessor Fund                                     17,599,630            (24,643,957)


Assuming the Reorganization had been completed on January 1, 2013, the pro forma
results of operations for the fiscal year ended December 31, 2013, were as
follows:



                                                                              
Net Investment income (loss)                                                     $ 21,022,659
Net realized and unrealized gains                                                 397,205,093
---------------------------------------------------------------------------------------------
Change in net assets resulting from operations                                   $418,227,752
---------------------------------------------------------------------------------------------


Because the combined investment portfolios have been managed as a single
integrated portfolio since the reorganization was completed, it is not practical
to separate the amounts of revenue and earnings of the Fund that have been
included in the Statements of Operations since the Reorganization was
consummated.

7. Line of Credit Facility

The Fund, along with certain other funds in the Pioneer Family of Funds (the
Funds), participates in a committed, unsecured revolving line of credit
facility. Borrowings are used solely for temporary or emergency purposes. The
Fund may borrow up to the lesser of the amount available under the facility or
the limits set for borrowing by the Fund's prospectus and the 1940 Act. The
credit facility in effect until February 12, 2014 was in the amount of $215
million. As of February 12, 2014, the facility is in the amount of $240 million.
Under such facility, depending on the type of loan, interest on borrowings is
payable at the

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 37


London Interbank Offered Rate (LIBOR) plus 0.90% (0.85% as of February 12, 2014)
on an annualized basis, or the Alternate Base Rate, which is the greater of (a)
the facility's administrative agent's daily announced prime rate on the
borrowing date, (b) 2% plus the Federal Funds Rate on the borrowing date and (c)
2% plus the overnight Eurodollar rate on the borrowing date. The Funds pay an
annual commitment fee to participate in a credit facility. The commitment fee is
allocated among participating Funds based on an allocation schedule set forth in
the credit agreement. For the year ended December 31, 2014, the Fund had no
borrowings under a credit facility.

8. Change in Independent Registered Public Accounting Firm

The Board of Trustees of the Fund, with the approval and recommendation of the
Audit Committee, appointed Deloitte & Touche LLP to serve as the Fund's
independent registered public accounting firm for the fiscal year ending
December 31, 2014. Deloitte & Touche LLP replaces Ernst & Young LLP, which
resigned as the Fund's independent registered public accounting firm, effective
upon completion of the audit of the Fund's financial statements for the fiscal
year ended December 31, 2013.

During the periods that Ernst & Young LLP served as the Fund's independent
registered public accounting firm, including the Fund's two most recent fiscal
years ending December 31, 2013 and December 31, 2012, Ernst & Young LLP's
reports on the financial statements of the Fund have not contained an adverse
opinion or disclaimer of opinion and have not been qualified or modified as to
uncertainty, audit scope or accounting principles. Further, there have been no
disagreements with Ernst & Young LLP on any matter of accounting principles or
practices, financial statement disclosure, or auditing scope or procedure,
which, if not resolved to the satisfaction of Ernst & Young LLP would have
caused Ernst & Young LLP to make reference to the subject matter of the
disagreement in connection with its report on the financial statements. In
addition, there have been no reportable events of the kind described in Item
304(a)(1)(v) of Regulation S-K under the Securities Exchange Act of 1934.

9. Conversion of Class B shares

As of the close of business on November 10, 2014 (the "Conversion Date"), all
outstanding Class B shares of the Fund were converted to Class A shares.

38 Pioneer Core Equity Fund | Annual Report | 12/31/14


Report of Independent Registered Public Accounting Firm

To the Board of Trustees and Shareowners of
Pioneer Core Equity Fund:
--------------------------------------------------------------------------------
We have audited the accompanying statement of assets and liabilities, including
the schedule of investments, of Pioneer Core Equity Fund (the "Fund"), as of
December 31, 2014, and the related statements of operations and changes in net
assets, and the financial highlights for the year then ended. These financial
statements and financial highlights are the responsibility of the Fund's
management. Our responsibility is to express an opinion on these financial
statements and financial highlights based on our audit. The statement of changes
in net assets of the Fund for the year ended December 31, 2013, and the
financial highlights for the years ended December 31, 2013, 2012, 2011, and 2010
were audited by other auditors. Those auditors expressed an unqualified opinion
on those financial statements and financial highlights in their report dated
February 25, 2014.

We conducted our audit 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. The Fund
is not required to have, nor were we engaged to perform, an audit of its
internal control over financial reporting. Our audit 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 Fund'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, assessing the accounting principles
used and significant estimates made by management, as well as evaluating the
overall financial statement presentation. Our procedures included confirmation
of securities owned as of December 31, 2014 by correspondence with the
custodian. We believe that our audit provides 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 Core Equity Fund as of December 31, 2014, and the results of its
operations, the changes in its net assets, and the financial highlights for the
year then ended, in conformity with accounting principles generally accepted in
the United States of America.

/s/ Deloitte & Touche LLP

Boston, Massachusetts
February 23, 2015

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 39


Approval of Investment Advisory Agreement

Pioneer Investment Management, Inc. (PIM) serves as the investment adviser to
Pioneer Core Equity Fund (the Fund) pursuant to an investment advisory agreement
between PIM and the Fund. In order for PIM to remain the investment adviser of
the Fund, the Trustees of the Fund must determine annually whether to renew the
investment advisory agreement for the Fund.

The contract review process began in January 2014 as the Trustees of the Fund
agreed on, among other things, an overall approach and timeline for the process.
Contract review materials were provided to the Trustees in March 2014 and July
2014. Supplemental contract review materials were provided to the Trustees in
September 2014. In addition, the Trustees reviewed and discussed the Fund's
performance at regularly scheduled meetings throughout the year, and took into
account other information related to the Fund provided to the Trustees at
regularly scheduled meetings, in connection with the review of the Fund's
investment advisory agreement.

In March 2014, the Trustees, among other things, discussed the memorandum
provided by Fund counsel that summarized the legal standards and other
considerations that are relevant to the Trustees in their deliberations
regarding the renewal of the investment advisory agreement, and reviewed and
discussed the qualifications of the investment management teams, as well as the
level of investment by the Fund's portfolio managers in the Fund. In July 2014,
the Trustees, among other things, reviewed the Fund's management fee and total
expense ratios, the financial statements of PIM and its parent companies, the
profitability analyses provided by PIM, and possible economies of scale. The
Trustees also reviewed the profitability of the institutional business of PIM
and PIM's affiliate, Pioneer Institutional Asset Management, Inc. (together with
PIM, "Pioneer"), as compared to that of PIM's fund management business, and
considered the differences between the fees and expenses of the Fund and the
fees and expenses of Pioneer's institutional accounts, as well as the different
services provided by PIM to the Fund and by Pioneer to the institutional
accounts. The Trustees further considered contract review materials in September
2014.

At a meeting held on September 16, 2014, based on their evaluation of the
information provided by PIM and third parties, the Trustees of the Fund,
including the Independent Trustees voting separately, unanimously approved the
renewal of the investment advisory agreement for another year. In considering
the renewal of the investment advisory agreement, the Trustees considered
various factors that they determined were relevant, including the factors
described below. In all quintile rankings referred to throughout this
disclosure, first quintile is most favorable to the Fund's shareowners. The
Trustees did not identify any single factor as the controlling factor in
determining to approve the renewal of the agreement.

40 Pioneer Core Equity Fund | Annual Report | 12/31/14


Nature, Extent and Quality of Services

The Trustees considered the nature, extent and quality of the services that had
been provided by PIM to the Fund, taking into account the investment objective
and strategy of the Fund. The Trustees reviewed the terms of the investment
advisory agreement. The Trustees also reviewed PIM's investment approach for the
Fund and its research process. The Trustees considered the resources of PIM and
the personnel of PIM who provide investment management services to the Fund.
They also reviewed the amount of non-Fund assets managed by the portfolio
managers of the Fund. The Trustees considered the non-investment resources and
personnel of PIM involved in PIM's services to the Fund, including PIM's
compliance and legal resources and personnel.

The Trustees noted the substantial attention and high priority given by PIM's
senior management to the Pioneer fund complex. The Trustees considered that PIM
supervises and monitors the performance of the Fund's service providers and
provides the Fund with personnel (including Fund officers) and other resources
that are necessary for the Fund's business management and operations. The
Trustees also considered that, as administrator, PIM is responsible for the
administration of the Fund's business and other affairs. The Trustees considered
the fees paid to PIM for the provision of administration services.

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

Performance of the Fund

In considering the Fund's performance, the Trustees regularly review and discuss
analysis and data prepared by PIM and information comparing the Fund's
performance with the performance of its peer group of funds as classified by
each of Morningstar, Inc. (Morningstar) and Lipper, and with the performance of
the Fund's benchmark index. They also discuss the Fund's performance with PIM on
a regular basis. The Trustees confirmed that these regular reviews and
discussions were factored into the Trustees' deliberations concerning the
renewal of the advisory agreement. For purposes of their contract renewal
deliberations, the Trustees considered the discussions held throughout the year
regarding the Fund's performance and the performance results of the Fund over
various time periods, including the Fund's performance results for periods ended
June 30, 2014. The Trustees indicated that they were satisfied with PIM's
investment discipline and approach in the prevailing market conditions,
notwithstanding relatively poor peer comparisons of total return over the 1-, 3-
and 5-year periods.

Management Fee and Expenses

The Trustees considered information showing the fees and expenses of the Fund in
comparison to the management fees and expense ratios of its peer group of funds
as classified by Morningstar and also to the expense ratios of a

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 41


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 Fund Research and Consulting, LLC (Strategic Insight), an independent
third party.

The Trustees considered that the Fund's management fee for the twelve months
ended June 30, 2014 was in the first quintile relative to the management fees
paid by other funds in its Morningstar peer group for the comparable period. The
Trustees considered that the expense ratio of the Fund's Class A shares for the
twelve months ended June 30, 2014 was in the second quintile relative to its
Morningstar peer group and in the first quintile relative its Strategic Insight
peer group, in each case for the comparable period. The Trustees considered the
impact of transfer agency, sub-transfer agency, and other non-management fee
expenses on the expense ratios of the Fund. The Trustees noted that they
separately review the Fund's transfer agency, sub-transfer agency and
intermediary arrangements.

The Trustees reviewed management fees charged by Pioneer to institutional and
other clients, including publicly offered European funds sponsored by affiliates
of Pioneer, unaffiliated U.S. registered investment companies (in a sub-advisory
capacity), and unaffiliated foreign and domestic separate accounts. The Trustees
also considered PIM's costs in providing services to the Fund and Pioneer's
costs in providing services to the other clients and considered the differences
in management fees and profit margins for Fund and non-Fund services. In
evaluating the fees associated with Pioneer's client accounts, the Trustees took
into account the respective demands, resources and complexity associated with
the Fund and client accounts. The Trustees noted that, in some instances, the
fee rates for those clients were lower than the management fee for the Fund and
considered that, under the investment advisory agreement with the Fund, PIM
performs additional services for the Fund that it does not provide to those
other clients or services that are broader in scope, including oversight of the
Fund's other service providers and activities related to compliance and the
extensive regulatory and tax regimes to which the Fund is subject. The Trustees
also considered the different entrepreneurial risks associated with PIM's
management of the Fund and Pioneer's management of the other client accounts.

The Trustees concluded that the management fee payable by the Fund to PIM was
reasonable in relation to the nature and quality of the services provided by PIM
to the Fund.

Profitability
The Trustees considered information provided by PIM regarding the profitability
of PIM with respect to the advisory services provided by PIM to the Fund,
including the methodology used by PIM in allocating certain of its costs to the
management of the Fund. The Trustees also considered PIM's profit margin in
connection with the overall operation of the Fund. They further reviewed the
financial results realized by PIM and its affiliates from

42 Pioneer Core Equity Fund | Annual Report | 12/31/14


non-fund businesses. The Trustees considered PIM's profit margins with
respect to the Fund 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 concluded that PIM's profitability with respect to the management of
the Fund was not unreasonable.

Economies of Scale

The Trustees considered PIM's views relating to economies of scale in connection
with the Pioneer Funds as fund assets grow and the extent to which any such
economies of scale are shared with funds and fund shareholders. The Trustees
recognize that economies of scale are difficult to identify and quantify, and
that, among other factors that may be relevant, are the following: fee levels,
expense subsidization, investment by PIM in research and analytical capabilities
and PIM's commitment and resource allocation to the Fund. The Trustees noted
that profitability also may be an indicator of the availability of any economies
of scale, although profitability may vary for other reasons including reductions
in expenses. The Trustees concluded that economies of scale, if any, were being
appropriately shared with the Funds.

Other Benefits

The Trustees considered the other benefits to PIM from its relationship with the
Fund. The Trustees considered the character and amount of fees paid by the Fund,
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. Pioneer is the
principal U.S. asset management business of Pioneer Global Asset Management, the
worldwide asset management business of UniCredit Group, which manages over $150
billion in assets (including the Funds). Pioneer and the Funds receive
reciprocal intangible benefits from the relationship, including mutual brand
recognition and, for the Funds, direct and indirect access to the resources of a
large global asset manager. The Trustees concluded that any such benefits
received by Pioneer as a result of its relationship with the Funds were
reasonable and their consideration of the advisory agreement between the Fund
and PIM and the fees thereunder were unaffected by Pioneer's possible receipt of
any such intangible benefits.

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 Fund, including the fees
payable thereunder, was fair and reasonable and voted to approve the proposed
renewal of the investment advisory agreement for the Fund.

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 43


Trustees, Officers and Service Providers

Investment Adviser
Pioneer Investment Management, Inc.

Custodian and Sub-Administrator
Brown Brothers Harriman & Co.

Independent Registered Public Accounting Firm
Deloitte & Touche LLP

Principal Underwriter
Pioneer Funds Distributor, Inc.

Legal Counsel
Morgan, Lewis & Bockius LLP

Shareowner Services and Transfer Agent
Pioneer Investment Management Shareholder Services, Inc.

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

Trustees and Officers

The Fund's Trustees and officers are listed below, together with their principal
occupations during at least the past five years. Trustees who are interested
persons of the Fund within the meaning of the 1940 Act are referred to as
Interested Trustees. Trustees who are not interested persons of the Fund are
referred to as Independent Trustees. Each of the Trustees serves as a Trustee of
each of the 52 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 Fund is 60 State Street, Boston, Massachusetts 02109.

The Statement of Additional Information of the Fund includes additional
information about the Trustees and is available, without charge, upon request,
by calling 1-800-225-6292.

44 Pioneer Core Equity Fund | Annual Report | 12/31/14


Independent Trustees



-----------------------------------------------------------------------------------------------------------------------------------
Name, Age and                 Term of Office and                                                Other Directorships
Position Held with the Fund   Length of Service           Principal Occupation                  Held by Trustee
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                       
Thomas J. Perna (64)          Trustee since 2006. Serves  Private investor (2004 - 2008 and     Director, Broadridge Financial
Chairman of the Board         until a successor trustee   2013 - present); Chairman (2008 -     Solutions, Inc. (investor
and Trustee                   is elected or earlier       2013) and Chief Executive Officer     communications and securities
                              retirement or removal.      (2008 - 2012), Quadriserv, Inc.       processing provider for financial
                                                          (technology products for securities   services industry) (2009 -
                                                          lending industry); and Senior         present); Director, Quadriserv,
                                                          Executive Vice President, The Bank    Inc. (2005 - 2013); and
                                                          of New York (financial and            Commissioner, New Jersey State
                                                          securities services) (1986 - 2004)    Civil Service Commission (2011 -
                                                                                                present)
-----------------------------------------------------------------------------------------------------------------------------------
David R. Bock (71)            Trustee since 2005. Serves  Managing Partner, Federal City        Director of New York Mortgage
Trustee                       until a successor trustee   Capital Advisors (corporate advisory  Trust (publicly-traded mortgage
                              is elected or earlier       services company) (1997 - 2004 and    REIT) 2004 - 2009, 2012 -
                              retirement or removal.      2008 - present); Interim Chief        present); Director (of The Swiss
                                                          Executive Officer, Oxford Analytica,  Helvetia Fund, Inc. (closed-end
                                                          Inc. (privately-held research and     fund) (2010 - present); Director
                                                          consulting company) (2010);           of Oxford Analytica, Inc. (2008 -
                                                          Executive Vice President and Chief    present); and Director of
                                                          Financial Officer, I-trax, Inc.       Enterprise Community Investment,
                                                          (publicly traded health care          Inc. (privately-held affordable
                                                          services company) (2004 - 2007); and  housing finance company) (1985 -
                                                          Executive Vice President and Chief    2010)
                                                          Financial Officer, Pedestal Inc.
                                                          (internet-based mortgage trading
                                                          company) (2000 - 2002); Private
                                                          consultant (1995-1997), Managing
                                                          Director, Lehman Brothers
                                                          (investment banking firm)
                                                          (1992-1995); and Executive, The
                                                          World Bank (1979-1992)
-----------------------------------------------------------------------------------------------------------------------------------
Benjamin M. Friedman (70)     Trustee since 2008. Serves  William Joseph Maier Professor of    Trustee, Mellon Institutional
Trustee                       until a successor trustee   Political Economy, Harvard           Funds Investment Trust and Mellon
                              is elected or earlier       University (1972 - present)          Institutional Funds Master
                              retirement or removal.                                           Portfolio (oversaw 17 portfolios
                                                                                               in fund complex) (1989-2008)
-----------------------------------------------------------------------------------------------------------------------------------


                          Pioneer Core Equity Fund | Annual Report | 12/31/14 45


Independent Trustees (continued)



-----------------------------------------------------------------------------------------------------------------------------------
Name, Age and                 Term of Office and                                                Other Directorships
Position Held with the Fund   Length of Service           Principal Occupation                  Held by Trustee
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                       
Margaret B.W. Graham (67)     Trustee since 1990. Serves  Founding Director, Vice President     None
Trustee                       until a successor trustee   and Corporate Secretary, The
                              is elected or earlier       Winthrop Group, Inc. (consulting
                              retirement or removal.      firm) (1982 - present); Desautels
                                                          Faculty of Management, McGill
                                                          University (1999 - present); and
                                                          Manager of Research Operations and
                                                          Organizational Learning, Xerox
                                                          PARC, Xerox's advance research
                                                          center (1990-1994)
-----------------------------------------------------------------------------------------------------------------------------------
Marguerite A. Piret (66)      Trustee since 1982. Serves  President and Chief Executive         Director of New America High
Trustee                       until a successor trustee   Officer, Newbury, Piret & Company,    Income Fund, Inc. (closed-end
                              is elected or earlier       Inc. (investment banking firm)        investment company) (2004 -
                              retirement or removal.      (1981 - present)                      present); and Member, Board of
                                                                                                Governors, Investment Company
                                                                                                Institute (2000 - 2006)
-----------------------------------------------------------------------------------------------------------------------------------
Fred J. Ricciardi (67)        Trustee since 2014. Serves  Consultant (investment company        None
Trustee                       until a successor trustee   services) (2012 - present);
                              is elected or earlier       Executive Vice President, BNY
                              retirement or removal.      Mellon (financial and investment
                                                          company services) (1969 - 2012);
                                                          Director, BNY International
                                                          Financing Corp. (financial
                                                          services) (2002 - 2012); and
                                                          Director, Mellon Overseas
                                                          Investment Corp. (financial
                                                          services) (2009 - 2012)
-----------------------------------------------------------------------------------------------------------------------------------


46 Pioneer Core Equity Fund | Annual Report | 12/31/14


Interested Trustee



-----------------------------------------------------------------------------------------------------------------------------------
Name, Age and                 Term of Office and                                                        Other Directorships
Position Held with the Fund   Length of Service           Principal Occupation                          Held by Trustee
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                               
Kenneth J. Taubes (56)*       Trustee since 2014. Serves  Director and Executive Vice President (since  None
Trustee                       until a successor trustee   2008) and Chief Investment Officer, U.S.
                              is elected or earlier       (since 2010) of PIM-USA; Executive Vice
                              retirement or removal.      President of Pioneer (since 2008); Executive
                                                          Vice President of Pioneer Institutional Asset
                                                          Management, Inc. (since 2009); and Portfolio
                                                          Manager of Pioneer (since 1999)
-----------------------------------------------------------------------------------------------------------------------------------


*    Mr. Taubes is an Interested Trustee because he is an officer of the Fund's
     investment adviser and certain of its affiliates.

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 47


Advisory Trustee



-----------------------------------------------------------------------------------------------------------------------------------
Name, Age and                 Term of Office and                                                               Other Directorships
Position Held with the Fund   Length of Service           Principal Occupation                                 Held by Trustee
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                                      
Lorraine Monchak (58)**       Advisory Trustee since      Chief Investment Officer, 1199 SEIU Funds            None
Advisory Trustee              2014.                       (healthcare workers union pension funds) (2001
                                                          - present); Vice President - International
                                                          Investments Group, American International
                                                          Group, Inc. (insurance company) (1993 - 2001);
                                                          Vice President Corporate Finance and Treasury
                                                          Group, Citibank, N.A.(1980 - 1986 and 1990 -
                                                          1993); Vice President - Asset/Liability
                                                          Management Group, Federal Farm Funding
                                                          Corporation (government-sponsored issuer of
                                                          debt securities) (1988 - 1990); Mortgage
                                                          Strategies Group, Shearson Lehman Hutton, Inc.
                                                          (investment bank) (1987 - 1988); and Mortgage
                                                          Strategies Group, Drexel Burnham Lambert, Ltd.
                                                          (investment bank) (1986 - 1987)
-----------------------------------------------------------------------------------------------------------------------------------


**   Ms. Monchak is a non-voting advisory trustee.

48 Pioneer Core Equity Fund | Annual Report | 12/31/14


Fund Officers



-----------------------------------------------------------------------------------------------------------------------------------
Name, Age and                 Term of Office and                                                           Other Directorships
Position Held with the Fund   Length of Service           Principal Occupation                             Held by Officer
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                                  
Lisa M. Jones (52)            Since 2014. Serves at the   Chair, Director, CEO and President of Pioneer    None
President and Chief           discretion of the Board     Investment Management-USA (since September
Executive Officer                                         2014); Chair, Director, CEO and President of
                                                          Pioneer Investment Management, Inc. (since
                                                          September 2014); Chair, Director, CEO and
                                                          President of Pioneer Funds Distributor, Inc.
                                                          (since September 2014); Chair, Director, CEO
                                                          and President of Pioneer Institutional Asset
                                                          Management, Inc. (since September 2014); and
                                                          Chair, Director, and CEO of Pioneer Investment
                                                          Management Shareholder Services, Inc. (since
                                                          September 2014); Managing Director, Morgan
                                                          Stanley Investment Management (2010 - 2013);
                                                          and Director of Institutional Business, CEO of
                                                          International, Eaton Vance Management (2005 -
                                                          2010)
-----------------------------------------------------------------------------------------------------------------------------------
Christopher J. Kelley (50)    Since 2003. Serves at the   Vice President and Associate General Counsel    None
Secretary and Chief           discretion of the Board.    of Pioneer since January 2008; Secretary and
Legal Officer                                             Chief Legal Officer of all of the Pioneer
                                                          Funds since June 2010; Assistant Secretary of
                                                          all of the Pioneer Funds from September 2003
                                                          to May 2010; and Vice President and Senior
                                                          Counsel of Pioneer from July 2002 to December
                                                          2007
-----------------------------------------------------------------------------------------------------------------------------------
Carol B. Hannigan (53)        Since 2010. Serves at the   Fund Governance Director of Pioneer since       None
Assistant Secretary           discretion of the Board.    December 2006 and Assistant Secretary of all
                                                          the Pioneer Funds since June 2010; Manager -
                                                          Fund Governance of Pioneer from December 2003
                                                          to November 2006; and Senior Paralegal of
                                                          Pioneer from January 2000 to November 2003
-----------------------------------------------------------------------------------------------------------------------------------
Thomas Reyes (52)             Since 2010. Serves at the   Senior Counsel of Pioneer since May 2013 and    None
Assistant Secretary           discretion of the Board.    Assistant Secretary of all the Pioneer Funds
                                                          since June 2010; and Counsel of Pioneer from
                                                          June 2007 to May 2013
-----------------------------------------------------------------------------------------------------------------------------------
Mark E. Bradley (55)          Since 2008. Serves at the   Vice President - Fund Treasury of Pioneer;      None
Treasurer and Chief           discretion of the Board.    Treasurer of all of the Pioneer Funds since
Financial and                                             March 2008; Deputy Treasurer of Pioneer from
Accounting Officer                                        March 2004 to February 2008; and Assistant
                                                          Treasurer of all of the Pioneer Funds from
                                                          March 2004 to February 2008
-----------------------------------------------------------------------------------------------------------------------------------


                          Pioneer Core Equity Fund | Annual Report | 12/31/14 49


Fund Officers (continued)



-----------------------------------------------------------------------------------------------------------------------------------
Name, Age and                 Term of Office and                                                          Other Directorships
Position Held with the Fund   Length of Service           Principal Occupation                            Held by Officer
-----------------------------------------------------------------------------------------------------------------------------------
                                                                                                 
Luis I. Presutti (49)         Since 2000. Serves at the   Director - Fund Treasury of Pioneer; and        None
Assistant Treasurer           discretion of the Board.    Assistant Treasurer of all of the Pioneer
                                                          Funds
-----------------------------------------------------------------------------------------------------------------------------------
Gary Sullivan (56)            Since 2002. Serves at the   Fund Accounting Manager - Fund Treasury of      None
Assistant Treasurer           discretion of the Board.    Pioneer; and Assistant Treasurer of all of the
                                                          Pioneer Funds
-----------------------------------------------------------------------------------------------------------------------------------
David F. Johnson (35)         Since 2009. Serves at the   Fund Administration Manager - Fund Treasury of  None
Assistant Treasurer           discretion of the Board.    Pioneer since November 2008; Assistant
                                                          Treasurer of all of the Pioneer Funds since
                                                          January 2009; and Client Service Manager -
                                                          Institutional Investor Services at State
                                                          Street Bank from March 2003 to March 2007
-----------------------------------------------------------------------------------------------------------------------------------
Jean M. Bradley (62)          Since 2010. Serves at the   Chief Compliance Officer of Pioneer and of all  None
Chief Compliance Officer      discretion of the Board.    the Pioneer Funds since March 2010; Chief
                                                          Compliance Officer of Pioneer Institutional
                                                          Asset Management, Inc. since January 2012;
                                                          Chief Compliance Officer of Vanderbilt Capital
                                                          Advisors, LLC since July 2012: Director of
                                                          Adviser and Portfolio Compliance at Pioneer
                                                          since October 2005; and Senior Compliance
                                                          Officer for Columbia Management Advisers, Inc.
                                                          from October 2003 to October 2005
-----------------------------------------------------------------------------------------------------------------------------------
Kelly O'Donnell (43)          Since 2006. Serves at the   Director - Transfer Agency Compliance of        None
Anti-Money Laundering Officer discretion of the Board.    Pioneer and Anti-Money Laundering Officer of
                                                          all the Pioneer Funds since 2006
-----------------------------------------------------------------------------------------------------------------------------------


50 Pioneer Core Equity Fund | Annual Report | 12/31/14


                           This page for your notes.

                          Pioneer Core Equity Fund | Annual Report | 12/31/14 51


                           This page for your notes.

52 Pioneer Core Equity Fund | Annual Report | 12/31/14


How to Contact Pioneer

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

Call us for:
--------------------------------------------------------------------------------
Account Information, including existing accounts,
new accounts, prospectuses, applications
and service forms                                                 1-800-225-6292

FactFone(SM) for automated fund yields, prices,
account information and transactions                              1-800-225-4321

Retirement plans information                                      1-800-622-0176

Write to us:
--------------------------------------------------------------------------------
PIMSS, Inc.
P.O. Box 55014
Boston, Massachusetts 02205-5014

Our toll-free fax                                                 1-800-225-4240

Our internet e-mail address                   ask.pioneer@pioneerinvestments.com
(for general questions about Pioneer only)


Visit our web site: us.pioneerinvestments.com

This report must be preceded or accompanied by a prospectus.

The Fund files a complete schedule of investments with the Securities and
Exchange Commission for the first and third quarters for each fiscal year on
Form N-Q. Shareholders may view the filed Form N-Q by visiting the Commission's
web site at http://www.sec.gov. The filed form may also 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.


[LOGO] PIONEER
       Investments(R)

Pioneer Investment Management, Inc.
60 State Street
Boston, MA 02109
us.pioneerinvestments.com

Securities offered through Pioneer Funds Distributor, Inc.
60 State Street, Boston, MA 02109
Underwriter of Pioneer Mutual Funds, Member SIPC
(C) 2015 Pioneer Investments 18630-09-0215


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 12(a)(1), 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 (see attachment);

        (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
The audit services provided to the Fund were totaled
approximately $22,869 payable to Deloitte & Touche
LLP for the year ended December 31, 2014 and $30,187
were paid to the former auditor, Ernst & Young LLP
for the year ended December 31, 2013.

(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 and Other Fees
There were no audit related fees and other fees for
the Trust payable to Deloitte & Touche LLP for
the year ended December 31, 2014 and no audit related
fees and other fees were paid to the former auditor,
Ernst & Young LLP for the year ended December 31, 2013.

(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 $5,600 payable to
Deloitte & Touche LLP for the year ended December 31,
2014 and $8,131 were paid to the former auditor,
Ernst & Young LLP for the year ended December 31, 2013.

(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.

Audit-Related Fees and Other Fees
There were no audit related fees and other fees for
the Trust payable to Deloitte & Touche LLP for
the year ended December 31, 2014 and no audit related
fees and other fees were paid to the former auditor,
Ernst & Young LLP for the year ended December 31, 2013.

(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.

Non-Audit Services
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 December 31, 2014
and 2013, 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 accountants 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 registrants accountant
for services rendered to the registrant, and rendered to the registrants
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.

Aggregate Non-Audit Fees
The aggregate non-audit fees for the Trust were $5,600
December 31, 2014 and $8,131 were paid to the former
auditor, Ernst & Young LLP for the year ended December 31,
2013.

(h) Disclose whether the registrants audit committee of the board of trustees
has considered whether the provision of non-audit services that were rendered to
the registrants 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 Trust'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 registrant's audit committee as specified in
Section 3(a)(58)(B) of the Exchange Act (15 U.S.C. 78c(a)(58)(B)),
so state.

N/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 of Investments in securities of unaffiliated issuers
as of the close of the reporting period as set forth in 210.1212
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.

Not applicable to open-end management investment companies.



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 registrant's portfolio ("Portfolio Manager"). Also state each Portfolio
Manager's business experience during the past 5 years.


Not applicable to open-end management investment companies.


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 registrant's equity securities
that is registered by the registrant pursuant to Section 12 of the
Exchange Act (15 U.S.C. 781).

Not applicable to open-end management investment companies.


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 registrant's board of directors, where
those changes were implemented after the registrant last provided
disclosure in response to the requirements of Item 407(c)(2)(iv) of
Regulation S-R(17 CFR 229.407)(as required by Item 22(b)(15))
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 registrant's board of
directors since the registrant last provided disclosure in response
to the requirements of Item 407(c)(2)(iv) of Regulation S-R 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 and
principal financials officers, or persons performing similar functions,
regarding the effectiveness of the registrant's disclosure
controls and procedures (as defined in Rule 30a-3(c) under the Act (17 CFR
270.30a-3(c))) as of a date within 90 days of the filing date of the report
that includes the disclosure required by this paragraph,
based on the evaluation of these controls and procedures required by Rule
30a-3(b) under the Act (17 CFR 270.30(a)-3(b) and Rules 13a-15(b) or 15d-15(b)
under the Exchange Act (17 CFR 240.13a-15(b) or 240.15d-15(b)).

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


(b) Disclose any change in the registrant's internal control over financial
reporting (as defined in Rule 30a-3(d) under the Act (17CFR 270.30a-3(d)) that
occured during the second fiscal quarter of the period covered by this report
that has materially affected, or is reasonably likely to materially affect,
the registrant's internal control over financial reporting.

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.

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

(1) 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.



(2) A separate certification for each principal executive officer and principal
financial officer of the registrant as required by Rule 30a-2(a) under the Act
(17 CFR 270.30a-2(a)) , exactly as set forth below:

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 Series Trust XI


By (Signature and Title)* /s/ Lisa M. Jones
Lisa M. Jones, President & Chief Executive Officer

Date February 27, 2015


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/ Lisa M. Jones
Lisa M. Jones, President & Chief Executive Officer

Date February 27, 2015


By (Signature and Title)* /s/ Mark Bradley
Mark Bradley, Treasurer & Chief Accounting & Financial Officer

Date February 27, 2015

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