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 811-21569

                          Pioneer Asset Allocation Trust
               (Exact name of registrant as specified in charter)


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


            Terrence J. Cullen, Amundi Pioneer Asset 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:  July 31


Date of reporting period:  August 1, 2017 through January 31, 2018


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 Solutions -- Balanced Fund

        Semiannual Report | January 31, 2018


        Ticker Symbols:

        Class A PIALX
        Class C PIDCX
        Class R BALRX
        Class Y IMOYX


[LOGO]    Amundi Pioneer
        ================
        ASSET MANAGEMENT



<page>
visit us: www.amundipioneer.com

<page>

Table of Contents


                                             
President's Letter                               2

Portfolio Management Discussion                  4

Portfolio Summary                               10

Prices and Distributions                        11

Performance Update                              12

Comparing Ongoing Fund Expenses                 20

Schedule of Investments                         22

Financial Statements                            25

Notes to Financial Statements                   34

Additional Information                          52

Trustees, Officers and Service Providers        54



              Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 1

<page>
President's Letter

While 2017 delivered strong positive performance, 2018, thus far, has
introduced market volatility. Concerns about the sustainability of the pace of
economic growth, extended equity valuations, and rising interest rates drove a
significant stock market sell-off beginning in late January, approaching
correction levels. As history has demonstrated time and time again, what goes
down, eventually bounces back, and this period has not been any different.

Our view is that the pause in the market's near-continuous upward momentum over
the previous 15 months presents an opportunity for investors to enter the
market at healthier valuation levels. We believe fundamentals are still quite
positive, yet also believe that caution is warranted given that the market
remains vulnerable to corrections. Some areas, such as growth stocks, appear
expensive, but we do see opportunity in value stocks, with prices supported by
better corporate earnings due to the recent tax reforms in the U.S. as well as
robust, nominal gross domestic product (GDP) growth. In fact, GDP growth in the
U.S. remained well above 2% in the fourth quarter of 2017, after rising to
better than 3% in the second and third quarters.

In the fixed-income markets, we believe investors should position their
portfolios to defend against rising interest rates, with underweight positions
in U.S. Treasuries. We see more attractive valuations within structured
investment vehicles, such as mortgage-backed securities (MBS) in both the
agency and non-agency residential MBS sectors, as fundamentals within the U.S.
housing market remain positive. We believe that agency MBS, in particular,
offer investors reasonable value.

Since 1928, the foundation of Amundi Pioneer's investment approach has been
active management, which is especially important during periods of market
volatility. We believe investors can benefit from the experience and tenure of
our investment teams who make active and informed decisions across our funds.
In fact, the Pioneer Fund, the third-oldest mutual fund in the U.S., recently
celebrated its 90th birthday. We believe the Fund serves as an important
ambassador of our time-tested value style of investing and our early focus on
understanding the benefits of investing in companies with sustainable business
models. Over its nine decades of existence -- a time period that included a
Great Depression, a devastating World War, a long Cold War, and enormous
technological as well as societal changes -- the Fund has been well-served by
this investment approach.

2 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
As always, and particularly during times of market uncertainty, 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.

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

/s/ Lisa M. Jones

Lisa M. Jones
Head of the Americas, President and CEO of U.S.
Amundi Pioneer Asset Management USA, Inc.
January 31, 2018

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. Past performance is no
guarantee of future results.

              Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 3

<page>
Portfolio Management Discussion | 1/31/18

In the following interview, portfolio managers Kenneth Taubes and Marco
Pirondini discuss the market environment and the investment strategies applied
to Pioneer Solutions -- Balanced Fund over the six-month period ended January
31, 2018. Working out of our Boston office, Mr. Taubes, Executive Vice
President, Chief Investment Officer, U.S., and a portfolio manager at Amundi
Pioneer Asset Management, Inc. (Amundi Pioneer), and Mr. Pirondini, Senior
Managing Director, Head of Equities, U.S., and a portfolio manager at Amundi
Pioneer, assumed responsibility for the day-to-day management of Pioneer
Solutions --Balanced Fund on January 26, 2018. Prior to January 26, 2018, the
Fund's management team was comprised of Paul Weber, John O'Toole, and Salvatore
Buono, working out of Amundi Pioneer's office in Dublin, Ireland.

Q    How did the Fund perform during the six-month period ended January 31,
     2018?

A    The Fund's Class A shares returned 6.87% at net asset value during the
     six-month period ended January 31, 2018, while the Fund's current blended
     benchmark returned 7.94% and the Fund's previous blended benchmark returned
     6.41%*. During the same period, the Fund's market benchmarks, the Bloomberg
     Barclays U.S. Aggregate Bond Index and the Morgan Stanley Capital
     International Index (MSCI) World ND Index1, returned -0.36% and 13.73%,
     respectively, while the average return of the 472 mutual funds in
     Morningstar's World Allocation Funds category was 8.05%.

Q    How would you characterize the economic and market backdrop during the
     six-month period ended January 31, 2018?

A    For much of the period, valuations for so-called "risk" assets were
     propelled higher by a backdrop of synchronized positive growth across major
     global economies, as conditions in Europe and Japan continued to
     strengthen.

1    The MSCI information may only be used for your internal use, may not be
     reproduced or redisseminated in any form and may not be used as a basis for
     or a component of any financial instruments or products or indices. None of
     the MSCI information is intended to constitute investment advice or a
     recommendation to make (or refrain from making) any kind of investment
     decision and may not be relied on as such. Historical data and analysis
     should not be taken as an indication or guarantee of any future performance
     analysis, forecast or prediction. The MSCI information is provided on an
     "as is" basis and the user of this information assumes the entire risk of
     any use made of this information. MSCI, each of its affiliates and each
     other person involved in or related to compiling, computing or creating any
     MSCI information (collectively, the "MSCI Parties") expressly disclaims all
     warranties (including, without limitation, any warranties of originality,
     accuracy, completeness, timeliness, non-infringement, merchantability and
     fitness for a particular purpose) with respect to this information. Without
     limiting any of the foregoing, in no event shall any MSCI Party have any
     liability for any direct, indirect, special, incidental, punitive,
     consequential (including, without limitation, lost profits) or any other
     damages.

*    Effective January 26, 2018, the Fund's blended benchmark is comprised of
     60% MSCI World ND Index/40% Bloomberg Barclays U.S. Aggregate Bond Index.
     Prior to January 26, 2018, the blended benchmark represented a 50%/50%
     split between the MSCI World ND Index and the Bloomberg Barclays U.S.
     Aggregate Bond Index.

4 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>

     In the U.S., after weighing in at a modest 1.2% for the first quarter of
     2017, gross domestic product (GDP) growth was measured at 3.0%, 3.1%, and
     2.6% over the succeeding three quarters of 2017. Corporate profit growth
     remained robust, while U.S. unemployment was gauged at 4.1% between October
     of 2017 and January of 2018, arguably reflecting an environment of full
     employment. Risk assets were provided a further boost in December 2017 as
     the U.S. Congress passed legislation lowering the corporate tax rate from
     35% to 21%, while also providing a window for companies to repatriate cash
     held overseas on favorable terms.

     Given the improvement in the U.S. economy, the U.S. Federal Reserve (the
     Fed) began to taper its bond portfolio in October, and in December
     instituted its third incremental interest-rate hike of 2017. Treasury
     yields rose along the length of the yield curve for the six-month period
     ended January 31, 2018, with the largest increases on shorter maturities.
     To illustrate, the two-year Treasury yield rose from 1.34% to 2.14% during
     the period, while the 30-year yield rose modestly, from 2.89% to 2.95%.

     Over the six months, global equities in aggregate returned 13.73%, as
     measured by the MSCI World ND Index. The U.S. equity market returned
     15.42%, as measured by the Standard & Poor's 500 Index, while developed
     market international equities returned 12.25%, as gauged by the MSCI
     Europe, Australasia, Far East Index. Emerging markets equities were very
     strong during the period, returning 18.67%, as indicated by the MSCI
     Emerging Markets Index.

     Within the U.S. equity market, growth stocks outperformed value, and
     large-cap stocks outperformed their small-cap counterparts. Fixed-income
     markets were weaker, however, as the Bloomberg Barclays U.S. Aggregate Bond
     Index, a widely used measure of the performance of the investment-grade
     U.S. bond market, returned -0.36% for the six-month period.

Q    What were the considerations and tactical shifts that were applied to the
     Fund in allocating assets during the six-month period ended January 31,
     2018?

A    As of January 26, 2018, the former Pioneer Solutions -- Conservative Fund
     and Pioneer Solutions -- Growth Fund were reorganized into Pioneer
     Solutions -- Balanced Fund, with shareholders of both funds receiving
     shares of Pioneer Solutions -- Balanced Fund. In conjunction with the
     reorganization, our team assumed responsibility for the day-to-day
     management of the Fund's portfolio.

              Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 5

<page>

     In broad terms, the Fund was positioned with a constructive view on risk
     assets over the six-month period. The extent of the Fund's overweight risk
     posture fluctuated during the period, peaking in late September before
     being trimmed in December 2017. Within the equity allocation, for most of
     the period the Fund's holdings were tilted toward Europe and Japan,
     relative to the U.S. On a style basis, the Fund's holdings reflected a
     preference for value relative to growth within the U.S. equity allocation.
     The portfolio also had some tactical positions in the emerging markets over
     the period, including in Korea, Russia, and China.

     With respect to the portfolio's fixed-income allocation, the Fund had an
     overweight exposure to credit-sensitive debt over the six-month period, as
     the incremental income available in the credit markets relative to other
     asset classes remained attractive. In terms of overall portfolio duration
     and corresponding sensitivity to changes in interest rates, the Fund had a
     conservative stance relative to the Bloomberg Barclays U.S. Aggregate Bond
     Index (the Bloomberg Barclays Index) for the majority of the period.
     However, in December the Fund's duration was moved closer to a neutral
     position relative to the Bloomberg Barclays Index. (Duration is a measure
     of the sensitivity of the price, or the value of principal, of a
     fixed-income investment to changes in interest rates, expressed as a number
     of years.)

Q    Which factors contributed positively to the Fund's benchmark-relative
     returns during the six-month period ended January 31, 2018, and which
     factors detracted from relative performance?

A    Security selection results within the Fund's exposure to global equities,
     particularly an allocation in Pioneer Global Equity Fund, contributed
     positively to relative performance. The Fund's overweight allocation to
     European and Japanese equities also aided relative returns, as those
     markets experienced strong performance over the six-month period. A
     relative value trade in which the Fund had a long position in European
     automobile companies versus the broader European equity market also
     performed well and aided the Fund's results.

     With respect to the Fund's fixed-income allocation, security selection
     within the U.S. was a positive contributor to returns, as both the core and
     flexible bond investment strategies outperformed. A relative value trade in
     which the Fund had a long position in the 10-year German bund relative to
     the comparable-maturity U.S. Treasury bond also contributed positively to
     performance, as did a long position in the Malaysian ringgit versus the
     U.S. dollar (USD).

     On the downside, security selection within the Fund's U.S. equity
     allocation constrained performance. A number of relative value trades also
     acted as drags on the Fund's returns. Specifically, a long position in U.S.
     versus

6 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>

     European interest rates, a long position in German equities relative to the
     broader European equity market, and a long position in the USD versus the
     euro each detracted from the Fund's performance.

Q    Did the Fund use derivative investments during the six-month period ended
     January 31, 2018? If so, did the derivatives have any effect on relative
     returns?

A    During the period, the Fund used derivatives in an effort to execute the
     management team's investment strategies in an efficient manner, including
     to gain or trim portfolio market exposures and to implement relative-value
     trades. In particular, during the six-month period we used derivatives to
     manage the portfolio's overlay duration and corresponding interest-rate
     sensitivity. As noted earlier, duration positioning had a neutral effect on
     relative performance.

Q    What factors are you watching most closely as you determine strategy for
     the Fund going forward?

A    Looking ahead to a new fiscal period for the Fund, we expect risk sentiment
     in the markets to continue to be supported by strong economic fundamentals.
     However, it would not be surprising to see an increase in volatility as we
     approach the end of a very long cycle of low interest rates and
     accommodative monetary policies from most global central banks. In
     addition, risk assets have experienced a lengthy period of inflows, which
     has led to extended valuations. This suggests that future returns are
     likely to be subdued relative to the recent past, and even compared with
     long-term averages.

     In managing the Fund, we will continue to utilize a broad selection of
     mutual funds in seeking to gain the desired portfolio exposures to U.S.
     equities, international equities, bonds, and cash, while targeting an
     overall asset allocation of 60% equity/40% fixed income going forward.

              Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 7

<page>
Please refer to the Schedule of Investments on pages 22-24 for a full listing
of fund securities.

All investments are subject to risk, including the possible loss of principal.
In the past several years, financial markets have experienced increased
volatility, depressed valuations, decreased liquidity and heightened
uncertainty. These conditions may continue, recur, worsen or spread.

Pioneer Solutions -- Balanced Fund is a "fund-of-funds" which seeks to achieve
its investment objectives by primarily investing in mainly funds managed by
Amundi Pioneer or one of its affiliates, rather than direct position in
securities. The Fund's performance depends on the adviser's skill in
determining the strategic asset allocations, the mix of underlying funds, as
well as the performance of those underlying funds. The underlying funds'
performance may be lower than the performance of the asset class that they were
selected to represent. In addition to the Fund's operating expenses, investors
will indirectly bear the operating expenses of investments in any underlying
funds. Each of the underlying funds has its own investment risks.

At times, the Fund's investments may represent industries or sectors that are
interrelated or have common risks, making them more susceptible to any
economic, political, or regulatory developments or other risks affecting those
industries and sectors. Investments in equity securities are subject to price
fluctuation.

When interest rates rise, the prices of fixed income securities in the Fund
will generally fall. Conversely, when interest rates fall, the prices of fixed
income securities in the Fund will generally rise.

Investments in the Fund are subject to possible loss due to the financial
failure of issuers of underlying securities and their inability to meet their
debt obligations.

Investing in foreign and/or emerging markets securities involves risks relating
to interest rates, currency exchange rates, economic, and political conditions.

The portfolios invests in real estate investment trust (REIT) securities, the
value of which can fall for a variety of reasons, such as declines in rental
income, fluctuating interest rates, poor property management, environmental
liabilities, uninsured damage, increased competition, or changes in real estate
tax laws.

The Fund may invest in underlying funds with exposure to commodities. The value
of commodity-linked derivatives may be affected by changes in overall market
movements, commodity index volatility, changes in interest rates, factors
affecting a particular industry or commodity, international economic, political
and regulatory developments, supply and demand, and governmental regulatory
policies.

8 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
The Fund may use derivatives, such as options, futures, inverse floating rate
obligations, swaps, and others, which can be illiquid, may disproportionately
increase losses, and have a potentially large impact on fund performance.
Derivatives may have a leveraging effect on the Fund.

The Fund may invest in credit default swaps, which may in some cases be
illiquid, and they increase credit risk since the fund has exposure to both the
issuer of the referenced obligation and the counterparty to the credit default
swap.

The Fund and some of the underlying funds employ leverage, which increases the
volatility of investment returns and subjects the Funds to magnified losses if
an underlying fund's investments decline in value. The Fund and some of the
underlying funds may employ short selling, a speculative strategy. Unlike the
possible loss on a security that is purchased, there is no limit on the amount
of loss on an appreciating security that is sold short.

The value of the investments held by the Fund for cash management or temporary
defensive purposes may be affected by market risks, changing interest rates,
and by changes in credit ratings of the investments. If the Fund holds cash
uninvested, the Fund will not earn income on the cash and the Fund's yield will
go down. These risks may increase share price volatility.

There is no assurance that these and other strategies used by the Fund will be
successful. Please see the prospectus for a more complete discussion of the
Fund's risks.

Before making an investment in any fund, you should consider all the risks
associated with it.

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

Any information in this shareowner report regarding market or economic trends
or the factors influencing each 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.

              Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 9
<page>
Portfolio Summary | 1/31/18

                               Asset Allocations
--------------------------------------------------------------------------------


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



                                     
Bonds                                   38.5%
International Equities                  31.5%
U.S. Equities                           30.0%



Actual Portfolio Holdings
--------------------------------------------------------------------------------
(As a percentage of total long-term holdings)*



                                               
Bonds
--------------------------------------------------------
Pioneer Strategic Income Fund Class K             10.60%
--------------------------------------------------------
Pioneer Bond Fund Class K                          9.43
--------------------------------------------------------
Pioneer Multi-Asset Income Fund Class K            4.21
--------------------------------------------------------
Pioneer Multi-Asset Ultrashort Income
 Fund Class K                                      4.02
--------------------------------------------------------
Doubleline Total Return Bond Fund Class I          2.63
--------------------------------------------------------
Pioneer Flexible Opportunity Fund Class Y          2.12
--------------------------------------------------------
Western Asset Core Plus Bond Fund
 Class IS                                          1.78
--------------------------------------------------------
MFS Total Return Bond Fund Class I                 1.75
--------------------------------------------------------
Pioneer Dynamic Credit Fund Class Y                0.88
--------------------------------------------------------
Pioneer Global High Yield Fund Class Y             0.59
--------------------------------------------------------
Metropolitan West Total Return Bond
 Fund Class I                                      0.51
--------------------------------------------------------
Pioneer High Yield Fund Class Y                    0.02
--------------------------------------------------------
International Equities
--------------------------------------------------------
Pioneer International Equity Fund
 Class Y                                          18.13%
--------------------------------------------------------
Pioneer Global Equity Fund Class K                12.32
--------------------------------------------------------
JOHCM Asia Ex-Japan Equity Fund
 Class IS                                          1.06
--------------------------------------------------------
U.S. Equities
--------------------------------------------------------
Pioneer Disciplined Value Fund Class Y             7.53%
--------------------------------------------------------
Pioneer Mid Cap Value Fund Class K                 5.89
--------------------------------------------------------
Pioneer Fundamental Growth Fund
 Class K                                           5.57
--------------------------------------------------------
Pioneer Core Equity Fund Class Y                   5.38
--------------------------------------------------------
Pioneer Fund Class Y                               4.79
--------------------------------------------------------
Oak Ridge Small Cap Growth Fund
 Class K                                           0.79
--------------------------------------------------------


Annual and semiannual reports for the underlying Pioneer funds may be obtained
on the funds' web page(s) at amundipioneer.com.

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

10 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
Prices and Distributions | 1/31/18



Net Asset Value per Share
                                                   
          Class                   1/31/18                 7/31/17
-----------------------------------------------------------------------
            A                     $12.48                  $11.89
-----------------------------------------------------------------------
            C                     $11.48                  $10.92
-----------------------------------------------------------------------
            R                     $12.41                  $11.83
-----------------------------------------------------------------------
            Y                     $12.65                  $12.06
-----------------------------------------------------------------------




Distributions per Share: 8/1/17--1/31/18
--------------------------------------------------------------------------------------
                                                              
                          Net Investment        Short-Term              Long-Term
          Class              Income            Capital Gains           Capital Gains
--------------------------------------------------------------------------------------
            A               $0.2221                $ --                    $ --
--------------------------------------------------------------------------------------
            C               $0.1393                $ --                    $ --
--------------------------------------------------------------------------------------
            R               $0.2056                $ --                    $ --
--------------------------------------------------------------------------------------
            Y               $0.2472                $ --                    $ --
--------------------------------------------------------------------------------------



Index Definitions
------------------------------------------------------------
The Morgan Stanley Capital International (MSCI) World ND Index is an unmanaged
measure of the performance of stock markets in the developed world. The
Bloomberg Barclays U.S. Aggregate Bond Index is an unmanaged measure of the
U.S. bond 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 indices defined here pertain to the "Value of $10,000 Investment" and
"Value of $5 Million Investment" charts on pages 12-19.

Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 11

<page>
Performance Update | 1/31/18                                      Class A Shares


Investment Returns
--------------------------------------------------------------------------------
The mountain chart below shows the change in value of a $10,000 investment made
in Class A shares of Pioneer Solutions -- Balanced Fund at public offering
price during the periods shown, compared to that of the MSCI World ND Index and
the Bloomberg Barclays U.S. Aggregate Bond Index, and the Fund's current and
former blended benchmarks.

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


Value of $10,000 Investment


                                                                Pioneer
                                Bloomberg                       Solutions -
                Pioneer         Barclays                        Current and
                Solutions -     U.S.                            Former
                Balanced        Aggregate       MSCI World      Blended
Dates           Fund            Bond Index      ND Index        Benchmark**
                                                    
1/08            $ 9,425         $10,000         $10,000         $10,000
1/09            $ 6,568         $10,259         $ 5,857         $ 7,825
1/10            $ 8,667         $11,131         $ 7,999         $ 9,577
1/11            $10,007         $11,695         $ 9,537         $10,774
1/12            $10,062         $12,708         $ 9,251         $11,108
1/13            $11,030         $13,036         $10,723         $12,144
1/14            $12,168         $13,052         $12,447         $13,109
1/15            $12,804         $13,916         $13,318         $14,010
1/16            $12,224         $13,893         $12,641         $13,679
1/17            $13,122         $14,095         $14,804         $14,926
1/18            $14,860         $14,398         $18,627         $16,917






Average Annual Total Returns
(As of January 31, 2018)
------------------------------------------------------------------------------------------------------------------------------------
                                                Current Blended           Former Blended
                                                Benchmark                 Benchmark
                                 Public         (60% MSCI World ND        (50% MSCI World ND         Bloomberg
                 Net Asset       Offering       Index/40% Bloomberg       Index/50% Bloomberg        Barclays
                 Value           Price          Barclays Aggregate        Barclays U.S. Aggregate    U.S. Aggregate     MSCI World
Period           (NAV)           (POP)          Bond Index)               Bond Index)                Bond Index         ND Index
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                      
10 years         4.66%           4.04%          5.67%                     5.40%                      3.71%               6.42%
5 years          6.14            4.89           7.84                      6.85                       2.01               11.68
1 year           13.25           6.74           15.85                     13.34                      2.15               25.83
------------------------------------------------------------------------------------------------------------------------------------


Expense Ratio
(Per prospectus dated December 1, 2017)
---------------------------------------------------
Gross
---------------------------------------------------
1.36%
---------------------------------------------------

Call 1-800-225-6292 or visit www.amundipioneer.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.

**   From January 31, 2008 through January 25, 2018, the Fund's former blended
     benchmark represented a 50%/50% split between the MSCI World ND Index and
     the Bloomberg Barclays Aggregate Bond Index. On January 26, 2018, the
     Fund's current blended benchmark changed to a mix of 60% MSCI World ND
     Index/40% Bloomberg Barclays Aggregate Bond Index.The mountain chart above
     reflects the growth of a single $10,000 investment in the Fund's blended
     benchmark over a 10-year period beginning in January 2008, and includes
     calculations for the Fund's former blended benchmark from January 2008
     through January 25, 2018, and for the Fund's current blended benchmark from
     January 26 through January 31, 2018.


(Please see the following page for additional performance and expense
disclosure)

12 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>
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 the 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 shown 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.

Effective January 26, 2018, the Fund compares its performance to a blended
benchmark consisting of 60% MSCI World ND Index and 40% Bloomberg Barclays U.S.
Aggregate Bond Index (the "current blended benchmark" shown in the performance
table on the previous page). Prior to January 26, 2018, the Fund compared its
performance to a blended benchmark consisting of 50% MSCI World ND Index and
50% Bloomberg Barclays U.S. Aggregate Bond Index (the "former blended
benchmark" shown in the performance table on the previous page). Amundi Pioneer
believes that the current blended benchmark better reflects the Fund's
investment strategies.

Please see the financial highlights for more recent expense ratios. Expense
ratios in the financial highlights, unlike those shown in the prospectus, do
not reflect acquired fund fees and expenses.

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.

Effective November 17, 2014, Amundi Pioneer became directly responsible for
portfolio management of the Fund. The performance shown for periods prior to
November 17, 2014, reflects the investment strategies employed during those
periods.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 13
<page>
Performance Update | 1/31/18                                      Class C Shares


Investment Returns
--------------------------------------------------------------------------------
The mountain chart below shows the change in value of a $10,000 investment made
in Class C shares of Pioneer Solutions -- Balanced Fund during the periods
shown, compared to that of the MSCI World ND Index and the Bloomberg Barclays
U.S. Aggregate Bond Index, and the Fund's current and former blended
benchmarks.

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


                                                                Pioneer
                                Bloomberg                       Solutions -
                Pioneer         Barclays                        Current and
                Solutions -     U.S.                            Former
                Balanced        Aggregate       MSCI World      Blended
                Fund            Bond Index      ND Index        Benchmark**
                                                    
1/08            $10,000         $10,000         $10,000         $10,000
1/09            $6,915          $10,259         $5,857          $7,825
1/10            $9,057          $11,131         $7,999          $9,577
1/11            $10,381         $11,695         $9,537          $10,774
1/12            $10,360         $12,708         $9,251          $11,108
1/13            $11,275         $13,036         $10,723         $12,144
1/14            $12,362         $13,052         $12,447         $13,109
1/15            $12,915         $13,916         $13,318         $14,010
1/16            $12,248         $13,893         $12,641         $13,679
1/17            $13,061         $14,095         $14,804         $14,926
1/18            $14,667         $14,398         $18,627         $16,917





Average Annual Total Returns
(As of January 31, 2018)
---------------------------------------------------------------------------------------------------------------------
                                      Current Blended       Former Blended
                                      Benchmark             Benchmark
                                      (60% MSCI World ND    (50% MSCI World ND         Bloomberg
                                      Index/40% Bloomberg   Index/50% Bloomberg        Barclays
             If          If           Barclays Aggregate    Barclays U.S. Aggregate    U.S. Aggregate     MSCI World
Period       Held        Redeemed     Bond Index)           Bond Index)                Bond Index         ND Index
---------------------------------------------------------------------------------------------------------------------
                                                                                        
10 years     3.90%       3.90%        5.67%                 5.40%                      3.71%               6.42%
5 years      5.40        5.40         7.84                  6.85                       2.01               11.68
1 year      12.29       12.29        15.85                 13.34                       2.15               25.83
---------------------------------------------------------------------------------------------------------------------


Expense Ratio
(Per prospectus dated December 1, 2017)
---------------------------------------
Gross
---------------------------------------
2.06%
---------------------------------------

Call 1-800-225-6292 or visit www.amundipioneer.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.

**   From January 31, 2008 through January 25, 2018, the Fund's former blended
     benchmark represented a 50%/50% split between the MSCI World ND Index and
     the Bloomberg Barclays Aggregate Bond Index. On January 26, 2018, the
     Fund's current blended benchmark changed to a mix of 60% MSCI World ND
     Index/40% Bloomberg Barclays Aggregate Bond Index.The mountain chart above
     reflects the growth of a single $10,000 investment in the Fund's blended
     benchmark over a 10-year period beginning in January 2008, and includes
     calculations for the Fund's former blended benchmark from January 2008
     through January 25, 2018, and for the Fund's current blended benchmark from
     January 26 through January 31, 2018.


(Please see the following page for additional performance and expense
disclosure)

14 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
Class C shares held for less than one year are also subject to a 1% contingent
deferred sales charge (CDSC). "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 shown 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.

Effective January 26, 2018, the Fund compares its performance to a blended
benchmark consisting of 60% MSCI World ND Index and 40% Bloomberg Barclays U.S.
Aggregate Bond Index (the "current blended benchmark" shown in the performance
table on the previous page). Prior to January 26, 2018, the Fund compared its
performance to a blended benchmark consisting of 50% MSCI World ND Index and
50% Bloomberg Barclays U.S. Aggregate Bond Index (the "former blended
benchmark" shown in the performance table on the previous page). Amundi Pioneer
believes that the current blended benchmark better reflects the Fund's
investment strategies.

Please see the financial highlights for more recent expense ratios. Expense
ratios in the financial highlights, unlike those shown in the prospectus, do
not reflect acquired fund fees and expenses.

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.

Effective November 17, 2014, Amundi Pioneer became directly responsible for
portfolio management of the Fund. The performance shown for periods prior to
November 17, 2014, reflects the investment strategies employed during those
periods.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 15

<page>
Performance Update | 1/31/18                                      Class R Shares


Investment Returns
--------------------------------------------------------------------------------
The mountain chart below shows the change in value of a $10,000 investment made
in Class R shares of Pioneer Solutions -- Balanced Fund during the periods
shown, compared to that of the MSCI World ND Index and the Bloomberg Barclays
U.S. Aggregate Bond Index, and the Fund's current and former blended
benchmarks.

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



Value of $10,000 Investment
                                                                                        Pioneer
                                        Bloomberg                                       Solutions -
                Pioneer                 Barclays                                        Current and
                Solutions -             U.S.                                            Former
                Balanced                Aggregate               MSCI World              Blended
                Fund                    Bond Index              ND Index                Benchmark**
                                                                            
1/08            $10,000                 $10,000                 $10,000                 $10,000
1/09            $ 6,968                 $10,259                 $5,857                  $7,825
1/10            $ 9,196                 $11,131                 $7,999                  $9,577
1/11            $10,618                 $11,695                 $9,537                  $10,774
1/12            $10,676                 $12,708                 $9,251                  $11,108
1/13            $11,703                 $13,036                 $10,723                 $12,144
1/14            $12,910                 $13,052                 $12,447                 $13,109
1/15            $13,585                 $13,916                 $13,318                 $14,010
1/16            $12,972                 $13,893                 $12,641                 $13,679
1/17            $13,891                 $14,095                 $14,804                 $14,926
1/18            $15,679                 $14,398                 $18,627                 $16,917




Average Annual Total Returns
(As of January 31, 2018)
-----------------------------------------------------------------------------------------------------------------------
                               Current Blended          Former Blended
                               Benchmark                Benchmark
                               (60% MSCI World ND       (50% MSCI World ND              Bloomberg
                               Index/40% Bloomberg      Index/50% Bloomberg             Barclays
               Net Asset       Barclays Aggregate       Barclays U.S. Aggregate         U.S. Aggregate     MSCI World
Period         Value (NAV)     Bond Index)              Bond Index)                     Bond Index         ND Index
-----------------------------------------------------------------------------------------------------------------------
                                                                                            
10 years       4.60%           5.67%                    5.40%                           3.71%               6.42%
5 years        6.03            7.84                     6.85                            2.01               11.68
1 year         12.88           15.85                    13.34                           2.15               25.83
-----------------------------------------------------------------------------------------------------------------------



Expense Ratio
(Per prospectus dated December 1, 2017)
---------------------------------------
                
Gross              Net
---------------------------------------
2.06%              1.58%
---------------------------------------


Call 1-800-225-6292 or visit www.amundipioneer.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.

**   From January 31, 2008 through January 25, 2018, the Fund's former blended
     benchmark represented a 50%/50% split between the MSCI World ND Index and
     the Bloomberg Barclays Aggregate Bond Index. On January 26, 2018, the
     Fund's current blended benchmark changed to a mix of 60% MSCI World ND
     Index/40% Bloomberg Barclays Aggregate Bond Index. The mountain chart above
     reflects the growth of a single $10,000 investment in the Fund's blended
     benchmark over a 10-year period beginning in January 2008, and includes
     calculations for the Fund's former blended benchmark from January 2008
     through January 25, 2018, and for the Fund's current blended benchmark from
     January 26 through January 31, 2018.

(Please see the following page for additional performance and expense
disclosure)

16 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
The performance shown for Class R shares for the period prior to the
commencement of operations of Class R shares on July 1, 2015, is the net asset
value performance of the Fund's Class A shares, which has not been restated to
reflect any differences in expenses, including Rule 12b-1 fees applicable to
Class A shares. Since fees for Class A shares generally are higher than those
of Class R shares, the performance of Class R shares prior to their inception
would have been higher than the performance shown. For the period beginning
July 1, 2015, the actual performance of Class R shares is reflected. Class R
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.

Effective January 26, 2018, the Fund compares its performance to a blended
benchmark consisting of 60% MSCI World ND Index and 40% Bloomberg Barclays U.S.
Aggregate Bond Index (the "current blended benchmark" shown in the performance
table on the previous page). Prior to January 26, 2018, the Fund compared its
performance to a blended benchmark consisting of 50% MSCI World ND Index and
50% Bloomberg Barclays U.S. Aggregate Bond Index (the "former blended
benchmark" shown in the performance table on the previous page). Amundi Pioneer
believes that the current blended benchmark better reflects the Fund's
investment strategies.

The net expense ratio reflects the contractual expense limitation currently in
effect through December 1, 2019, for Class R shares. There can be no assurance
that Amundi Pioneer will extend the expense limitation beyond such time. Please
see the prospectus and financial statements for more information.

Please see the financial highlights for more recent expense ratios. Expense
ratios in the financial highlights, unlike those shown in the prospectus, do
not reflect acquired fund fees and expenses.

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.

Effective November 17, 2014, Amundi Pioneer became directly responsible for
portfolio management of the Fund. The performance shown for periods prior to
November 17, 2014, reflects the investment strategies employed during those
periods.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 17

<page>

Performance Update | 1/31/18                                      Class Y Shares

Investment Returns
--------------------------------------------------------------------------------
The mountain chart below shows the change in value of a $5 million investment
made in Class Y shares of Pioneer Solutions -- Balanced Fund during the periods
shown, compared to that of the MSCI World ND Index and the Bloomberg Barclays
U.S. Aggregate Bond Index, and the Fund's current and former blended
benchmarks.

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

Value of $5 Million Investment


                                                                                        Pioneer
                                        Bloomberg                                       Solutions -
                Pioneer                 Barclays                                        Current and
                Solutions -             U.S.                                            Former
                Balanced                Aggregate               MSCI World              Blended
                Fund                    Bond Index              ND Index                Benchmark***
                                                                            
1/08            $5,000,000              $5,000,000              $5,000,000              $5,000,000
1/09            $3,514,182              $5,129,387              $2,928,467              $3,912,524
1/10            $4,672,245              $5,565,717              $3,999,730              $4,788,497
1/11            $5,417,083              $5,847,363              $4,768,300              $5,387,066
1/12            $5,465,991              $6,353,866              $4,625,648              $5,554,056
1/13            $6,009,168              $6,518,153              $5,361,561              $6,071,910
1/14            $6,648,060              $6,526,250              $6,223,273              $6,554,351
1/15            $7,014,726              $6,957,796              $6,658,805              $7,004,767
1/16            $6,715,859              $6,946,669              $6,320,428              $6,839,485
1/17            $7,228,772              $7,047,589              $7,401,941              $7,462,831
1/18            $8,203,027              $7,199,035              $9,313,585              $8,458,485




Average Annual Total Returns
(As of January 31, 2018)
-------------------------------------------------------------------------------------------------------------------
                               Current Blended           Former Blended
                               Benchmark                 Benchmark
                               (60% MSCI World ND        (50% MSCI World ND         Bloomberg
                               Index/40% Bloomberg       Index/50% Bloomberg        Barclays
              Net Asset        Barclays Aggregate        Barclays U.S. Aggregate    U.S. Aggregate     MSCI World
Period        Value (NAV)      Bond Index)               Bond Index)                Bond Index         ND Index
-------------------------------------------------------------------------------------------------------------------
                                                                                         
10 years      5.08%             5.67%                      5.40%                    3.71%                6.42%
5 years       6.42              7.84                       6.85                     2.01                11.68
1 year       13.48             15.85                      13.34                     2.15                25.83
-------------------------------------------------------------------------------------------------------------------


Expense Ratio
(Per prospectus dated December 1, 2017)
---------------------------------------
Gross
---------------------------------------
1.15%
---------------------------------------

Call 1-800-225-6292 or visit www.amundipioneer.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.

***  From January 31, 2008 through January 25, 2018, the Fund's former blended
     benchmark represented a 50%/50% split between the MSCI World ND Index and
     the Bloomberg Barclays Aggregate Bond Index. On January 26, 2018, the
     Fund's current blended benchmark changed to a mix of 60% MSCI World ND
     Index/40% Bloomberg Barclays Aggregate Bond Index. The mountain chart above
     reflects the growth of a single $5,000,000 investment in the Fund's blended
     benchmark over a 10-year period beginning in January 2008, and includes
     calculations for the Fund's former blended benchmark from January 2008
     through January 25, 2018, and for the Fund's current blended benchmark from
     January 26 through January 31, 2018.

(Please see the following page for additional performance and expense
disclosure)

18 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18

<page>
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 shown 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.

Effective January 26, 2018, the Fund compares its performance to a blended
benchmark consisting of 60% MSCI World ND Index and 40% Bloomberg Barclays U.S.
Aggregate Bond Index (the "current blended benchmark" shown in the performance
table on the previous page). Prior to January 26, 2018, the Fund compared its
performance to a blended benchmark consisting of 50% MSCI World ND Index and
50% Bloomberg Barclays U.S. Aggregate Bond Index (the "former blended
benchmark" shown in the performance table on the previous page). Amundi Pioneer
believes that the current blended benchmark better reflects the Fund's
investment strategies.

Please see the financial highlights for more recent expense ratios. Expense
ratios in the financial highlights, unlike those shown in the prospectus, do
not reflect acquired fund fees and expenses.

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.

Effective November 17, 2014, Amundi Pioneer became directly responsible for
portfolio management of the Fund. The performance shown for periods prior to
November 17, 2014, reflects the investment strategies employed during those
periods.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 19
<page>
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 [ ] $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 Solutions Balanced Fund

Based on actual returns from August 1, 2017 through January 31, 2018.



--------------------------------------------------------------------------------
Share Class                 A               C              R              Y
--------------------------------------------------------------------------------
                                                          
Beginning Account        $1,000.00      $1,000.00       $1,000.00     $1,000.00
Value on 8/1/17
--------------------------------------------------------------------------------
Ending Account Value     $1,068.70      $1,064.30       $1,066.80     $1,069.80
(after expenses)
on 1/31/18
--------------------------------------------------------------------------------
Expenses Paid            $    3.60      $    7.23       $    4.22     $    2.66
During Period*
--------------------------------------------------------------------------------


*    Expenses are equal to the Fund's annualized net expense ratio of 0.69%,
     1.39%, 0.83% and 0.51% for Class A, C, R and Y shares, respectively,
     multiplied by the average account value over the period, multiplied by
     184/365 to reflect the one half-year period. Fund expense ratios do not
     include estimates for acquired fund fees and expenses (AFFE). If AFFE
     estimates were included, expenses paid during the period would have been
     $7.14, $10.77, $7.87 and $6.21 for Class A, C, R and Y shares,
     respectively, based on the respective expense ratio for each class of
     1.37%, 2.07%, 1.51% and 1.19%.

20 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18

<page>
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 Solutions Balanced Fund

Based on a hypothetical 5% per year return before expenses, reflecting the
period from August 1, 2017 through January 31, 2018.



--------------------------------------------------------------------------------
Share Class                 A               C              R              Y
--------------------------------------------------------------------------------
                                                          
Beginning Account        $1,000.00      $1,000.00       $1,000.00     $1,000.00
Value on 8/1/17
--------------------------------------------------------------------------------
Ending Account Value     $1,021.73      $1,018.20       $1,021.12     $1,022.63
(after expenses)
on 1/31/18
--------------------------------------------------------------------------------
Expenses Paid            $    3.52      $    7.07       $    4.13     $    2.60
During Period*
--------------------------------------------------------------------------------


*    Expenses are equal to the Fund's annualized net expense ratio of 0.69%,
     1.39%, 0.83% and 0.51% for Class A, C, R and Y shares, respectively,
     multiplied by the average account value over the period, multiplied by
     184/365 to reflect the one half-year period. Fund expense ratios do not
     include estimates for acquired fund fees and expenses (AFFE). If AFFE
     estimates were included, expenses paid during the period would have been
     $6.97, $10.51, $7.68 and $6.06 for Class A, C, R and Y shares,
     respectively, based on the respective expense ratio for each class of
     1.37%, 2.07%, 1.51% and 1.19%.


             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 21

<page>
Schedule of Investments | 1/31/18 (unaudited)



------------------------------------------------------------------------------------------------------------------------------
                                                                Change
                                                                in Net
                                                 Net            Unrealized      Capital
                                                 Realized       Appreciation    Gain              Dividend
Shares                                           Gain (Loss)    (Depreciation)  Distributions     Income         Value
------------------------------------------------------------------------------------------------------------------------------
                                                                                               
                AFFILIATED ISSUERS -- 83.0%*
                MUTUAL FUNDS -- 83.0%
 4,876,375      Pioneer Bond Fund                $ (6,942)      $ (629,234)     $          --     $  245,343     $  46,959,491
                  Class K
 1,216,438      Pioneer Core Equity Fund               --         8,253,710           331,335         57,793        26,798,127
                  Class Y
 2,230,779      Pioneer Disciplined Value          15,312         2,057,498         1,090,887        116,607        37,477,087
                  Fund Class Y
  465,490       Pioneer Dynamic Credit             (8,531)          (71,895)               --        102,517         4,361,645
                  Fund Class Y
  732,218       Pioneer Flexible                       --                --                --             --        10,529,295
                  Opportunities Fund
                  Class Y
  772,756       Pioneer Fund Class Y                   --        (1,695,075)          762,552         25,456        23,847,242
 1,162,398      Pioneer Fundamental                    --         3,873,801           174,967         31,853        27,699,944
                  Growth Fund Class K
 3,575,749      Pioneer Global Equity              32,085        10,528,198           896,471        317,175        61,324,095
                  Fund Class K
  329,310       Pioneer Global High                    --            62,892                --         72,886         2,957,206
                 Yield Fund Class Y
   12,639       Pioneer High Yield Fund                --            48,484                --             29           123,607
                  Class Y
 3,496,168      Pioneer International             122,539        27,085,527                --        611,196        90,236,099
                  Equity Fund Class Y
 1,123,517      Pioneer Mid Cap Value                 394           786,934           447,973         48,272        29,335,029
                  Fund Class K
 1,711,491      Pioneer Multi-Asset                    --                --                --             --        20,948,650
                  Income Fund Class K
 2,006,000      Pioneer Multi-Asset                    --                --                --             --        19,999,820
                  Ultrashort Income Fund
                  Class K
 4,889,960      Pioneer Strategic Income               --            15,050                --        422,848        52,762,669
                  Fund Class K
------------------------------------------------------------------------------------------------------------------------------
                TOTAL INVESTMENTS IN
                AFFILIATED ISSUERS
                (Cost $390,082,309)              $154,857       $50,315,890     $    3,704,185    $2,051,975     $ 455,360,006
------------------------------------------------------------------------------------------------------------------------------


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

22 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>



                                                                   
------------------------------------------------------------------------------------
Shares                                                                Value
------------------------------------------------------------------------------------
                UNAFFILIATED ISSUERS -- 7.8%
                MUTUAL FUNDS -- 7.8%
1,245,150       Doubleline Total Return Bond Fund Class I             $  13,086,527
  396,219       JOHCM Asia Ex-Japan Equity Fund Class IS                  5,325,184
  240,697       Metropolitan West Total Return Bond Fund Class I          2,534,539
  823,733       MFS Total Return Bond Fund Class I                        8,739,807
  226,400       Oak Ridge Small Cap Growth Fund Class K                   3,932,568
  756,003       Western Asset Core Plus Bond Fund Class IS                8,860,355
------------------------------------------------------------------------------------
                TOTAL INVESTMENTS IN UNAFFILIATED ISSUERS
                (Cost $46,485,435)                                    $  42,478,980
------------------------------------------------------------------------------------
                OTHER ASSETS AND LIABILITIES -- 9.2%                  $  50,616,244
------------------------------------------------------------------------------------
                NET ASSETS -- 100.0%                                  $ 548,455,230
====================================================================================


* Affiliated funds managed by Amundi Pioneer Asset Management, Inc.

Purchases and sales of securities (excluding temporary cash investments) for
the six months ended January 31, 2018, were as follows:


--------------------------------------------------------------------------------
                                           Purchases          Sales
--------------------------------------------------------------------------------
                                                        
Long-Term U.S. Government Securities       $        --        $ 3,600,202
Other Long-term Securities                 $70,644,614        $85,667,069


The Fund is permitted to engage in purchase and sale transactions ("cross
trades") with certain funds and accounts for which Amundi Pioneer Asset
Management, Inc., formerly Pioneer Investment Management, Inc. (the "Adviser"),
serves as the Fund's investment adviser, as set forth in Rule 17a-7 under the
Investment Company Act of 1940, pursuant to procedures adopted by the Board of
Trustees. Under these procedures, cross trades are affected at current market
prices. During the six months ended January 31, 2018, the Fund did not engage
in cross trade activity-.

At January 31, 2018, the net unrealized appreciation on investments based on
cost for federal tax purposes of $437,341,523 was as follows:



                                                                      
   Aggregate gross unrealized appreciation for all investments in which
     there is an excess of value over tax cost                              $ 68,901,888

   Aggregate gross unrealized depreciation for all investments in which
     there is an excess of tax cost over value                                (8,404,425)
                                                                            ------------
   Net unrealized appreciation                                              $ 60,497,463
                                                                            ============


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

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 23

<page>
Schedule of Investments | 1/31/18 (unaudited) (continued)

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

The following is a summary of the inputs used as of January 31, 2018, in
valuing the Fund's assets:



--------------------------------------------------------------------------------
                   Level 1            Level 2       Level 3      Total
                                                     
--------------------------------------------------------------------------------
Mutual Funds       $497,838,986       $ --          $ --         $497,838,986
--------------------------------------------------------------------------------
Total              $497,838,986       $ --          $ --         $497,838,986
===============================================================================


During the six months ended January 31, 2018, there were no transfers between
Levels 1, 2, and 3.

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

24 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>


Statements of Assets and Liabilities | 1/31/18 (unaudited)
                                                                                   
ASSETS:
  Investments in securities of affiliated funds, at value (cost $ 390,082,309)        $455,360,006
  Investments in securities of unaffiliated funds, at value (cost $46,485,435)          42,478,980
  Cash                                                                                  47,851,735
  Receivables --
     Investment securities sold                                                         54,239,724
     Dividends                                                                             301,542
  Due from the Adviser                                                                          80
---------------------------------------------------------------------------------------------------
       Total assets                                                                   $600,232,067
---------------------------------------------------------------------------------------------------
LIABILITIES:
  Payables for:
     Investment securities purchased                                                    51,477,765
     Fund shares repurchased                                                                67,808
     Trustees' fees                                                                          1,040
  Due to affiliates                                                                         20,182
  Due to custodian                                                                           1,997
  Accrued expenses and other liabilities                                                   208,045
---------------------------------------------------------------------------------------------------
       Total liabilities                                                              $ 51,776,837
---------------------------------------------------------------------------------------------------
NET ASSETS:
  Paid-in capital                                                                     $482,188,012
  Distributions in excess of net investment income                                        (314,377)
  Accumulated net realized gain on investments                                           5,310,364
  Net unrealized appreciation on investments                                            61,271,231
---------------------------------------------------------------------------------------------------
       Net assets                                                                     $548,455,230
---------------------------------------------------------------------------------------------------
NET ASSET VALUE PER SHARE:
No par value (Unlimited number of shares authorized)
  Class A (based on $416,448,045/33,371,287 shares)                                   $      12.48
  Class C (based on $129,667,482/11,292,186 shares)                                   $      11.48
  Class R (based on $463,975/37,386 shares)                                           $      12.41
  Class Y (based on $1,875,728/148,325 shares)                                        $      12.65
MAXIMUM OFFERING PRICE:
  Class A (12.48 (divided by) 94.25)                                                  $      13.24
---------------------------------------------------------------------------------------------------


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

Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 25

<page>


Statements of Operations (unaudited)

For the Six Months Ended 1/31/18


                                                          
INVESTMENT INCOME:
  Dividend income from underlying affiliated funds           $ 2,051,975
  Dividend income from underlying unaffiliated funds             495,462
  Interest                                                        67,236
-------------------------------------------------------------------------
       Total Investment Income                               $ 2,614,673
-------------------------------------------------------------------------
EXPENSES:
  Management fees                                            $   105,618
  Administrative expense                                          41,798
  Transfer agent fees
     Class A                                                      43,654
     Class C                                                      11,973
     Class R                                                          73
     Class Y                                                         499
  Distribution fees
     Class A                                                     150,207
     Class C                                                     252,249
     Class R                                                         112
  Shareholder communications expense                              20,600
  Custodian fees                                                  22,680
  Registration fees                                               47,740
  Professional fees                                               39,662
  Printing expense                                                 1,490
  Pricing fees                                                     1,344
  Trustees' fees                                                   4,565
  Insurance expense                                                1,997
  Interest expense                                                 3,061
  Miscellaneous                                                   39,544
-------------------------------------------------------------------------
     Total expenses                                          $   788,866
     Less fees waived and expenses reimbursed
       by the Adviser                                        $      (108)
-------------------------------------------------------------------------
     Net expenses                                            $   788,758
-------------------------------------------------------------------------
       Net investment income                                 $ 1,825,915
-------------------------------------------------------------------------


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

26 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>

For the Six Months Ended 1/31/18

REALIZED AND UNREALIZED GAIN (LOSS) ON INVESTMENTS:
                                                                     
  Net realized gain (loss) on:
     Underlying affiliated funds                                        $    154,857
     Underlying unaffiliated funds                                         8,012,939
     Capital gain on distributions from underlying affiliated issuers      3,704,185
     Capital gain on distributions from underlying unaffiliated issuers      345,371
     Futures contracts                                                       (40,519)
     Swap contracts                                                          (92,107)
     Written options                                                           9,940
     Forward foreign currency contracts                                     (833,464)
     Other assets and liabilities denominated in foreign currencies         (104,257)
-------------------------------------------------------------------------------------
                                                                        $ 11,156,945
-------------------------------------------------------------------------------------
  Change in net unrealized appreciation (depreciation) on:
     Underlying affiliated funds                                        $ 50,315,890
     Underlying unaffiliated funds                                        (4,900,524)
     Futures contracts                                                        22,799
     Swap contracts                                                           86,792
     Forward foreign currency contracts                                      503,032
     Other assets and liabilities denominated in foreign currencies            7,442
-------------------------------------------------------------------------------------
                                                                        $ 46,035,431
-------------------------------------------------------------------------------------
  Net realized and unrealized gain (loss) on investments                $ 57,192,376
-------------------------------------------------------------------------------------
  Net increase in net assets resulting from operations                  $ 59,018,291
-------------------------------------------------------------------------------------


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

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 27

<page>
Statements of Changes in Net Assets (unaudited)



-------------------------------------------------------------------------------------------
                                                          Six Months
                                                          Ended            Year
                                                          1/31/18          Ended
                                                          (unaudited)      7/31/17
-------------------------------------------------------------------------------------------
                                                                     
FROM OPERATIONS:
Net investment income (loss)                              $     1,825,915  $     2,244,602
Net realized gain (loss) on investments                        11,156,945       (1,174,516)
Change in net unrealized appreciation (depreciation)
  on investments                                               46,035,431        9,956,749
-------------------------------------------------------------------------------------------
Net increase (decrease) in net assets resulting
  from operations                                         $    59,018,291  $    11,026,835
-------------------------------------------------------------------------------------------
DISTRIBUTIONS TO SHAREOWNERS:
Net investment income:
  Class A ($0.22 and $0.24, respectively)                 $    (2,088,405) $    (2,480,991)
  Class C ($0.14 and $0.16, respectively)                        (598,301)        (853,099)
  Class R ($0.21 and $0.23, respectively)                            (584)            (382)
  Class Y ($0.25 and $0.27, respectively)                         (12,552)         (20,656)
-------------------------------------------------------------------------------------------
     Total distributions to shareowners                   $    (2,699,842) $    (3,355,128)
-------------------------------------------------------------------------------------------
FROM FUND SHARE TRANSACTIONS:
Net proceeds from sales or exchange of shares             $    12,036,682  $    22,714,830
Shares issued in reorganization*                              384,986,563               --
Reinvestment of distributions                                   2,600,109        3,207,879
Cost of shares repurchased                                    (72,020,355)     (55,233,494)
-------------------------------------------------------------------------------------------
     Net increase (decrease) in net assets resulting from
       Fund share transactions                                327,602,999      (29,310,785)
-------------------------------------------------------------------------------------------
     Net increase (decrease) in net assets                $   383,921,448  $   (21,639,078)
NET ASSETS:
Beginning of period                                           164,533,782      186,172,860
-------------------------------------------------------------------------------------------
End of period                                             $   548,455,230  $   164,533,782
-------------------------------------------------------------------------------------------
Undistributed (distributions in excess of) net investment
  income, end of period                                   $      (314,377) $       559,550
-------------------------------------------------------------------------------------------

* See Notes to Financial Statements (Note 8).

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

28 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>


------------------------------------------------------------------------------------------------------
                                  Six Months      Six Months
                                  Ended           Ended
                                  1/31/18         1/31/18              Year Ended      Year Ended
                                  Shares          Amount               7/31/17         7/31/17
                                  (unaudited)     (unaudited)          Shares          Amount
------------------------------------------------------------------------------------------------------
                                                                           
Class A
Shares sold                          551,379      $    6,761,698        1,036,619      $   11,837,739
Shares issued in
  reorganization*                 23,831,150         301,225,732               --                  --
Reinvestment of distributions        167,680           2,050,726          221,988           2,448,547
Less shares repurchased             (808,505)        (50,228,884)      (2,695,716)        (30,690,063)
------------------------------------------------------------------------------------------------------
     Net increase
        (decrease)                23,741,704      $  259,809,272       (1,437,109)     $  (16,403,777)
------------------------------------------------------------------------------------------------------
Class C
Shares sold                          434,566      $    4,901,420          977,713      $   10,240,742
Shares issued in
  reorganization*                  7,074,294          82,274,035               --                  --
Reinvestment of distributions         48,099             541,592           72,790             741,003
Less shares repurchased             (775,327)        (21,308,616)      (2,234,082)        (23,459,634)
------------------------------------------------------------------------------------------------------
     Net increase
        (decrease)                 6,781,632      $   66,408,431       (1,183,579)     $  (12,477,889)
------------------------------------------------------------------------------------------------------
Class R
Shares sold                           27,253      $      339,721            1,293      $       14,650
Shares issued in
  reorganization*                     13,344             167,732               --                  --
Reinvestment of distributions             35                 423               18                 201
Less shares repurchased               (5,836)            (96,903)              (3)                (40)
------------------------------------------------------------------------------------------------------
     Net increase                     34,796      $      410,973            1,308      $       14,811
------------------------------------------------------------------------------------------------------
Class Y
Shares sold                            2,698      $       33,843           53,810      $      621,699
Shares issued in
  reorganization*                    102,971           1,319,064               --                  --
Reinvestment of distributions            595               7,368            1,623              18,128
Less shares repurchased              (15,842)           (385,952)         (93,660)         (1,083,757)
------------------------------------------------------------------------------------------------------
     Net increase (decrease)          90,422      $      974,323          (38,227)     $     (443,930)
------------------------------------------------------------------------------------------------------
* See Notes to Financial Statements (Note 8).


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

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 29

<page>


Financial Highlights
------------------------------------------------------------------------------------------------------------------------------------
                                                               Six Months
                                                               Ended        Year       Year         Year        Year       Year
                                                               1/31/18      Ended      Ended        Ended       Ended      Ended
                                                               (unaudited)  7/31/17    7/31/16*     7/31/15*    7/31/14*   7/31/13
------------------------------------------------------------------------------------------------------------------------------------
                                                                                                         
 Class A
 Net asset value, beginning of period                          $  11.89     $  11.35   $  12.78     $  12.73    $  11.72   $  10.46
------------------------------------------------------------------------------------------------------------------------------------
 Increase (decrease) from investment operations:
   Net investment income (a)                                   $   0.14     $   0.17   $   0.20     $   0.29    $   0.19   $   0.21
   Net realized and unrealized gain (loss) on investments          0.67         0.61      (0.50)        0.12        1.03       1.27
------------------------------------------------------------------------------------------------------------------------------------
 Net increase (decrease) from investment operations            $   0.81     $   0.78   $  (0.30)    $   0.41    $   1.22   $   1.48
------------------------------------------------------------------------------------------------------------------------------------
 Distributions to shareowners:
   Net investment income                                       $  (0.22)    $  (0.24)  $  (0.27)    $  (0.36)   $  (0.21)  $  (0.22)
   Net realized gain                                                 --           --      (0.86)          --          --         --
------------------------------------------------------------------------------------------------------------------------------------
 Total distributions to shareowners                            $  (0.22)    $  (0.24)  $  (1.13)    $  (0.36)   $  (0.21)  $  (0.22)
------------------------------------------------------------------------------------------------------------------------------------
 Net increase (decrease) in net asset value                    $   0.59     $   0.54   $  (1.43)    $   0.05    $   1.01   $   1.26
------------------------------------------------------------------------------------------------------------------------------------
 Net asset value, end of period                                $  12.48     $  11.89   $  11.35     $  12.78    $  12.73   $  11.72
------------------------------------------------------------------------------------------------------------------------------------
 Total return (b)                                                  6.87%(c)     7.04%     (2.11)%       3.33%      10.48%     14.32%
 Ratio of net expenses to average net assets+                      0.69%(d)     0.68%      0.67%        0.66%       0.64%      0.66%
 Ratio of net investment income to average net assets+             2.23%(d)     1.51%      1.77%        2.25%       1.57%      1.85%
 Portfolio turnover rate                                             34%(c)       27%        16%          89%         10%         9%
 Net assets, end of period (in thousands)                      $416,448     $114,528   $125,608     $140,863    $136,511   $128,425
 Ratios with no waivers of fees and assumption of expenses by
   the Adviser, and no reduction for fees paid indirectly:
   Total expenses to average net assets                            0.69%(d)     0.68%      0.67%        0.66%       0.64%      0.66%
   Net investment income to average net assets                     2.23%(d)     1.51%      1.77%        2.25%       1.57%      1.85%
------------------------------------------------------------------------------------------------------------------------------------


*    The Fund was audited by an independent registered public accounting firm
     other than Ernst & Young LLP.

+    In addition to the expenses which the Fund bears directly, the Fund
     indirectly bears pro rata shares of the expenses of the funds in which the
     Fund invests. Because each of the underlying funds bears its own varying
     expense levels and because the Fund may own differing proportions of each
     fund at different times, the amount of expenses incurred indirectly by the
     Fund will vary from time to time.

(a)  Calculated using average shares outstanding for the period.

(b)  Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions and 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.

(c)  Not annualized.

(d)  Annualized.

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

30 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18

<page>


-------------------------------------------------------------------------------------------------------------------------------
                                                              Six Months
                                                              Ended        Year       Year      Year       Year       Year
                                                              1/31/18      Ended      Ended     Ended      Ended      Ended
                                                              (unaudited)  7/31/17    7/31/16*  7/31/15*   7/31/14*   7/31/13
-------------------------------------------------------------------------------------------------------------------------------
                                                                                                       
Class C
Net asset value, beginning of period                          $  10.92     $  10.44   $  11.84  $  11.82   $  10.92   $   9.77
-------------------------------------------------------------------------------------------------------------------------------
Increase (decrease) from investment operations:
  Net investment income (a)                                   $   0.10     $   0.09   $   0.12  $   0.17   $   0.09   $   0.12
  Net realized and unrealized gain (loss) on investments          0.60         0.55      (0.47)     0.14       0.96       1.19
-------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) from investment operations            $   0.70     $   0.64   $  (0.35) $   0.31   $   1.05   $   1.31
-------------------------------------------------------------------------------------------------------------------------------
Distributions to shareowners:
  Net investment income                                       $  (0.14)    $  (0.16)  $  (0.19) $  (0.29)  $  (0.15)  $  (0.16)
  Net realized gain                                                 --           --      (0.86)       --         --         --
-------------------------------------------------------------------------------------------------------------------------------
Total distributions to shareowners                            $  (0.14)    $  (0.16)  $  (1.05) $  (0.29)  $  (0.15)  $  (0.16)
-------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net asset value                    $   0.56     $   0.48   $  (1.40) $   0.02   $   0.90   $   1.15
-------------------------------------------------------------------------------------------------------------------------------
Net asset value, end of period                                $  11.48     $  10.92   $  10.44  $  11.84   $  11.82   $  10.92
-------------------------------------------------------------------------------------------------------------------------------
Total return (b)                                                  6.43%(c)     6.26%     (2.81)%    2.64%      9.70%     13.56%
Ratio of net expenses to average net assets+                      1.39%(d)     1.38%      1.37%     1.35%      1.33%      1.34%
Ratio of net investment income to average net assets+             1.66%(d)     0.84%      1.10%     1.44%      0.81%      1.15%
Portfolio turnover rate                                             34%(c)       27%        16%       89%        10%         9%
Net assets, end of period (in thousands)                      $129,667     $ 49,277   $ 59,444  $ 74,720   $ 75,377   $ 64,989
Ratios with no waivers of fees and assumption of expenses by
  the Adviser and no reduction for fees paid indirectly:
  Total expenses to average net assets                            1.39%(d)     1.38%      1.37%     1.35%      1.33%      1.34%
  Net investment income to average net assets                     1.66%(d)     0.84%      1.10%     1.44%      1.44%      1.15%
-------------------------------------------------------------------------------------------------------------------------------


*    The Fund was audited by an independent registered public accounting firm
     other than Ernst & Young LLP.

+    In addition to the expenses which the Fund bears directly, the Fund
     indirectly bears pro rata shares of the expenses of the funds in which the
     Fund invests. Because each of the underlying funds bears its own varying
     expense levels and because the Fund may own differing proportions of each
     fund at different times, the amount of expenses incurred indirectly by the
     Fund will vary from time to time.

(a)  Calculated using average shares outstanding for the period.

(b)  Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions and 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.

(c)  Not annualized.

(d)  Annualized.


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

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 31
<page>


Financial Highlights (continued)
---------------------------------------------------------------------------------------------------------------
                                                              Six Months
                                                              Ended        Year       Year
                                                              1/31/18      Ended      Ended      7/1/15 to
                                                              (unaudited)  7/31/17    7/31/16*   7/31/15*
---------------------------------------------------------------------------------------------------------------
                                                                                       
 Class R
 Net asset value, beginning of period                         $  11.83     $  11.30   $  12.78   $  12.74
---------------------------------------------------------------------------------------------------------------
 Increase (decrease) from investment operations:
   Net investment income (a)                                  $   0.03     $   0.11   $   0.15   $   0.01
   Net realized and unrealized gain (loss) on investments         0.76         0.65      (0.47)      0.03
---------------------------------------------------------------------------------------------------------------
 Net increase (decrease) from investment operations           $   0.79     $   0.76   $  (0.32)  $   0.04
---------------------------------------------------------------------------------------------------------------
 Distributions to shareowners:
   Net investment income                                      $  (0.21)    $  (0.23)  $  (0.30)  $     --
   Net realized gain                                                --           --      (0.86)        --
---------------------------------------------------------------------------------------------------------------
 Total distributions to shareowners                           $  (0.21)    $  (0.23)  $  (1.16)  $     --
---------------------------------------------------------------------------------------------------------------
 Net increase (decrease) in net asset value                   $   0.58     $   0.53   $  (1.48)  $   0.04
---------------------------------------------------------------------------------------------------------------
 Net asset value, end of period                               $  12.41     $  11.83   $  11.30   $  12.78
---------------------------------------------------------------------------------------------------------------
 Total return (b)                                                 6.68%(c)     6.89%     (2.34)%      0.31%(c)
 Ratio of net expenses to average net assets+                     0.83%(d)     0.90%      0.90%      0.93%(d)
 Ratio of net investment income to average net assets+            0.36%(d)     0.98%      1.28%      0.66%(d)
 Portfolio turnover rate                                            34%(c)       27%        16%        89%
 Net assets, end of period (in thousands)                     $    464     $     31   $     14   $     10
 Ratios with no waivers of fees and assumption of expenses by
   the Adviser and no reduction for fees paid indirectly:
   Total expenses to average net assets                           1.26%(d)     1.38%      1.58%      1.00%(d)
   Net investment income to average net assets                   (0.07)%(d)    0.50%      0.60%      0.58%(d)
---------------------------------------------------------------------------------------------------------------


*    The Fund was audited by an independent registered public accounting firm
     other than Ernst & Young LLP.

+    In addition to the expenses which the Fund bears directly, the Fund
     indirectly bears pro rata shares of the expenses of the funds in which the
     Fund invests. Because each of the underlying funds bears its own varying
     expense levels and because the Fund may own differing proportions of each
     fund at different times, the amount of expenses incurred indirectly by the
     Fund will vary from time to time.

(a)  Calculated using average shares outstanding for the period.

(b)  Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions and the complete redemption of
     the investment at net asset value at the end of each period.

(c)  Not annualized.

(d)  Annualized.


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

32 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18

<page>


-------------------------------------------------------------------------------------------------------------------------------
                                                             Six Months
                                                             Ended        Year       Year       Year       Year       Year
                                                             1/31/18      Ended      Ended      Ended      Ended      Ended
                                                             (unaudited)  7/31/17    7/31/16*   7/31/15*   7/31/14*   7/31/13
-------------------------------------------------------------------------------------------------------------------------------
                                                                                                    
Class Y
Net asset value, beginning of period                         $  12.06     $  11.51   $  12.94   $  12.88   $  11.86   $  10.58
-------------------------------------------------------------------------------------------------------------------------------
Increase (decrease) from investment operations:
  Net investment income (a)                                  $   0.16     $   0.19   $   0.26   $   0.37   $   0.23   $   0.25
  Net realized and unrealized gain (loss) on investments         0.68         0.63      (0.53)      0.09       1.03       1.28
-------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) from investment operations           $   0.84     $   0.82   $  (0.27)  $   0.46   $   1.26   $   1.53
-------------------------------------------------------------------------------------------------------------------------------
Distributions to shareowners:
  Net investment income                                      $  (0.25)    $  (0.27)  $  (0.30)  $  (0.40)  $  (0.24)  $  (0.25)
  Net realized gain                                                --           --      (0.86)        --         --         --
-------------------------------------------------------------------------------------------------------------------------------
Total distributions to shareowners                           $  (0.25)    $  (0.27)  $  (1.16)  $  (0.40)  $  (0.24)  $  (0.25)
-------------------------------------------------------------------------------------------------------------------------------
Net increase (decrease) in net asset value                   $   0.59     $   0.55   $  (1.43)  $   0.06   $   1.02   $   1.28
-------------------------------------------------------------------------------------------------------------------------------
Net asset value, end of period                               $  12.65     $  12.06   $  11.51   $  12.94   $  12.88   $  11.86
-------------------------------------------------------------------------------------------------------------------------------
Total return (b)                                                 6.98%(c)     7.33%     (1.85)%     3.63%     10.68%     14.68%
Ratio of net expenses to average net assets+                     0.51%(d)     0.47%      0.40%      0.36%      0.40%      0.36%
Ratio of net investment income to average net assets+            2.48%(d)     1.67%      2.22%      2.92%      1.88%      2.26%
Portfolio turnover rate                                            34%(c)       27%        16%        89%        10%         9%
Net assets, end of period (in thousands)                     $  1,876     $    698   $  1,107   $  1,165   $  3,239   $  4,134
Ratios with no waivers of fees and assumption of expenses by
  the Adviser and no reduction for fees paid indirectly:
  Total expenses to average net assets                           0.51%(d)     0.47%      0.40%      0.36%      0.40%      0.36%
  Net investment income to average net assets                    2.48%(d)     1.67%      2.22%      2.92%      1.88%      2.26%
-------------------------------------------------------------------------------------------------------------------------------


*    The Fund was audited by an independent registered public accounting firm
     other than Ernst & Young LLP.

+    In addition to the expenses which the Fund bears directly, the Fund
     indirectly bears pro rata shares of the expenses of the funds in which the
     Fund invests. Because each of the underlying funds bears its own varying
     expense levels and because the Fund may own differing proportions of each
     fund at different times, the amount of expenses incurred indirectly by the
     Fund will vary from time to time.

(a)  Calculated using average shares outstanding for the period.

(b)  Assumes initial investment at net asset value at the beginning of each
     period, reinvestment of all distributions and the complete redemption of
     the investment at net asset value at the end of each period.

(c)  Not annualized.

(d)  Annualized.


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

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 33

<page>
Notes to Financial Statements | 1/31/18 (unaudited)

1. Organization and Significant Accounting Policies

Pioneer Solutions -- Balanced Fund (the "Fund" is the sole series of Pioneer
Asset Allocation Trust (the "Trust") a Delaware statutory trust. The Fund is
registered with the Securities and Exchange Commission under the Investment
Company Act of 1940 (the 1940 Act) as an open-end management investment
company. The investment objective of the Fund is to seek long-term capital
growth and current income.

The Fund is a "fund of funds". The Fund seeks to achieve its investment
objective by investing primarily in other funds ("underlying funds"). The Fund
may also invest directly in securities and use derivatives. The Fund invests
mainly in funds managed by Amundi Pioneer Asset Management, Inc. The Fund may
also invest in unaffiliated mutual funds or exchange-traded funds (ETFs). The
Fund indirectly pay a portion of the expenses incurred by underlying funds.
Consequently, an investment in the Fund entails more direct and indirect
expenses than direct investment in the applicable underlying funds.

The Fund offers four classes of shares designated as Class A, Class C, Class R
and Class Y shares. 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 of
Trustees the flexibility to specify either per-share voting or dollar-weighted
voting when submitting matters for shareowner approval. Under per-share voting,
each share of a class of the Fund is entitled to one vote. Under
dollar-weighted voting, a shareowner'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.

On July 3, 2017, Amundi acquired Pioneer Investments, a group of asset
management companies located throughout the world. Amundi, one of the world's
largest asset managers, is headquartered in Paris, France. As a result of the
transaction, Pioneer Investment Management, Inc., the Funds' investment
adviser, became an indirect wholly owned subsidiary of Amundi and Amundi's

34 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
wholly owned subsidiary, Amundi USA, Inc. Prior to July 3, 2017, Pioneer
Investments was owned by Pioneer Global Asset Management S.p.A., a wholly owned
subsidiary of UniCredit S.p.A.

In connection with the transaction, the names of the Fund's investment adviser
and principal underwriter changed. Effective July 3, 2017, the name of Pioneer
Investment Management, Inc. changed to Amundi Pioneer Asset Management, Inc.
(the "Adviser") and the name of Pioneer Funds Distributor, Inc. changed to
Amundi Pioneer Distributor, Inc (the "Distributor").

The Fund's financial statements have been prepared in conformity with U.S.
generally accepted accounting principles (U.S. GAAP) that require the
management of the Fund to make estimates and assumptions that affect the
reported amounts of assets and liabilities at the date of the financial
statements and the reported amounts of income and expenses during the reporting
period. Actual results could differ from these estimates.

The Fund is an investment company and follows investment company accounting and
reporting guidance under U.S. GAAP. The following is a summary of significant
accounting policies followed by the Fund in the preparation of these financial
statements:

A.   Security Valuation

     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.

     Shares of open-end registered investment companies (including money market
     mutual funds) are valued at such funds' net asset value. Repurchase
     agreements are valued at par. Cash may include overnight time deposits at
     approved financial institutions.

     Fixed-income securities are valued by using prices supplied by independent
     pricing services, which consider such factors as market prices, market
     events, quotations from one or more brokers, Treasury spreads, yields,
     maturities and ratings, or may use a pricing matrix or other fair value
     methods or techniques to provide an estimated value of the security or
     instrument. A pricing matrix is a means of valuing a debt security on the
     basis of current market prices for other debt securities, historical
     trading patterns in the market for fixed income securities and/or other
     factors. Non-U.S. debt securities that are listed on an exchange will be
     valued at the bid price obtained from an independent third party pricing
     service. When independent third party pricing services are unable to supply
     prices, or when prices or market quotations are considered to be
     unreliable, the value of that security may be determined using quotations
     from one or more broker-dealers.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 35

     <page>

     Swap contracts, including interest rate swaps, caps and floors (other than
     centrally cleared swap contracts) are valued at the dealer quotations
     obtained from reputable International Swap Dealers Association members.
     Centrally cleared swaps are valued at the daily settlement price provided
     by the central clearing counterparty.

     Futures contracts are generally valued at the closing settlement price
     established by the exchange on which they are traded.

     Options contracts are generally valued at the mean between the last bid and
     ask prices on the principal exchange where they are traded.
     Over-the-counter ("OTC") options and options on swaps ("swaptions") are
     valued using prices supplied by independent pricing services, which
     consider such factors as market prices, market events, quotations from one
     or more brokers, Treasury spreads, yields, maturities and ratings, or may
     use a pricing matrix or other fair value methods or techniques to provide
     an estimated value of the security or instrument.

     Forward foreign currency exchange contracts are valued daily using the
     foreign exchange rate or, for longer term forward contract positions, the
     spot currency rate, in each case provided by a third party pricing service.
     Contracts whose forward settlement date falls between two quoted days are
     valued by interpolation.

     Securities for which independent pricing services or broker-dealers 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 the Adviser pursuant
     to procedures adopted by the Fund's Board of Trustees. The Adviser's fair
     valuation team uses fair value methods approved by the Valuation Committee
     of the Board of Trustees. The Adviser'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 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 Fund's securities may differ significantly from exchange prices and such
     differences could be material.

36 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>

     At January 31, 2018, the Fund held no securities valued using fair value
     methods (other than to securities valued using prices supplied by
     independent pricing services, broker-dealers or using a third party
     insurance industry pricing model).

B.   Investment Income and Transactions

     Dividend income and realized capital gain distributions from investment
     company shares held are recorded on the ex-dividend date. 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.

     Security transactions are recorded as of trade date. 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 price 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 record 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 contracts and from unanticipated
     movements in the value of foreign currencies relative to the U.S. dollar.


             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 37

<page>

     During the six months ended January 31, 2018, the Fund had entered into
     various forward foreign currency contracts that obligate the Fund to
     deliver or take delivery of currencies at specified future maturity dates.
     Alternatively, prior to the settlement date of a forward foreign currency
     contract, the Fund may close out such contract by entering into an
     offsetting contract.

     The average value of contracts open during the six months ended January 31,
     2018, was $52,906,699.

     At January 31, 2018, the Fund had no open forward foreign currency
     contracts.

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 taxable income and net realized capital gains, if any, to shareowners.
     Therefore, no federal income tax provisions are required. Tax years for the
     prior three fiscal 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. GAAP. 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 July 31, 2017, the Fund was permitted to carry forward $4,426,631 of
     short-term capital losses and $353,901 of long-term capital losses without
     limitations.

     The tax character of current year distributions paid will be determined at
     the end of the current taxable year. The tax character of distributions
     paid during the year ended July 31, 2017 were as follows:



                                             2017
----------------------------------------------------
                                      
----------------------------------------------------
Distributions paid from:
Ordinary income                          $3,335,128
----------------------------------------------------
    Total                                $3,335,128
----------------------------------------------------


38 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>

     The following table shows the components of distributable earnings on a
     federal income tax basis at July 31, 2017:

     
     
                                         
     Distributable earnings:
     Undistributed ordinary income          $    69,192
     Capital loss carryforward               (4,780,532)
     Unrealized appreciation/(depreciation)  14,660,109
     ---------------------------------------------------
         Total                              $ 9,948,769
     ---------------------------------------------------
     

     The differences between book-basis and tax-basis net unrealized
     appreciation/(depreciation) are attributable to the tax deferral of losses
     on wash sales.

F.   Fund Shares

     The Fund record sales and repurchases of its shares as of trade date. The
     Distributor, the principal underwriter for the Fund, earned $6,932 in
     underwriting commissions on the sale of Class A shares during the
     six months ended January 31, 2018.

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 Fund, respectively (see Note
     4). Class Y shares do not pay distribution fees. All expenses and fees paid
     to the Fund's transfer agent, for its services are allocated among the
     class 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, Class R and Class Y shares
     can reflect different transfer agent and distribution expense rates.

H.   Risks

     The value of securities held by the Fund may go up or down, sometimes
     rapidly or unpredictably, due to general market conditions, such as real or
     perceived adverse economic, political or regulatory conditions, inflation,
     changes in interest rates, lack of liquidity in the bond markets or adverse
     investor sentiment. In the past several years, financial markets have


     Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 39

<page>

     experienced increased volatility, depressed valuations, decreased liquidity
     and heightened uncertainty. These conditions may continue, recur, worsen or
     spread.

     Interest rates in the U.S. recently have been historically low, so the Fund
     faces a heightened risk that interest rates may rise. A general rise in
     interest rates could adversely affect the price and liquidity of fixed
     income securities and could also result in increased redemptions from the
     Fund.

     Some of the underlying funds can invest in either high yield securities or
     small/emerging growth companies. Investments in these types of securities
     generally are subject to greater volatility than either higher-grade
     securities or more established companies in more developed markets,
     respectively. The Funds' prospectus contains unaudited information
     regarding the Funds' principal risks. Please refer to that document when
     considering the Funds' principal risks.

I.   Futures Contracts

     The Fund may enter into futures transactions in order to attempt to hedge
     against changes in interest rates, securities prices and currency exchange
     rates or to seek to increase total return. Futures contracts are types of
     derivatives. All futures contracts entered into by the Fund are traded on a
     futures exchange. Upon entering into a futures contract, the Fund is
     required to deposit with a broker an amount of cash or securities equal to
     the minimum "initial margin" requirements of the associated futures
     exchange. The amount of cash deposited with the broker as collateral, if
     any, at January 31, 2018 is recorded within "Futures collateral" in the
     Statement of Assets and Liabilities.

     Subsequent payments for futures contracts ("variation margin") are paid or
     received by the Fund, depending on the daily fluctuation in the value of
     the contracts, and are recorded by the Fund as unrealized appreciation or
     depreciation. When the contract is closed, the Fund realize a gain or loss
     equal to the difference between the opening and closing value of the
     contract as well as any fluctuation in foreign currency exchange rates
     where applicable. Future contracts are subject to market risk, interest
     risk and currency risk. Changes in value of the contracts may not directly
     correlate to the changes in value of the underlying securities. With
     futures, there is minimal counterparty credit risk to the Fund since
     futures are exchange-traded and the exchange's clearinghouse, as
     counterparty to all exchange-traded futures, guarantees the futures against
     default. The average value of contracts open during the six months ended
     January 31, 2018, was $(21,208,784).

     At January 31, 2018, the Fund had no open future contracts.

40 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>

J.   Option Writing

     The Fund may write put and covered call options to seek to increase total
     return. When an option is written, the Fund receive a premium and become
     obligated to purchase or sell the underlying security at a fixed price upon
     the exercise of the option. When the Fund write an option, an amount equal
     to the premium received by the Fund is recorded as a liability and is
     subsequently adjusted to the current value of the option written. Premiums
     received from writing options that expire unexercised are treated by the
     Fund on the expiration date as realized gains from investments. The
     difference between the premium and the amount paid on effecting a closing
     purchase transaction, including brokerage commissions, is also treated as a
     realized gain or, if the premium is less than the amount paid for the
     closing purchase transaction, as a realized loss. If a call option is
     exercised, the premium is added to the proceeds from the sale of the
     underlying security in determining whether the Fund has realized a gain or
     loss. The Fund, as writer of an option, bears the market risk of an
     unfavorable change in the price of the security underlying the written
     option.

     Written call and put option contracts outstanding at period end, if any,
     are listed at the end of Fund's Schedule of Investments. The average value
     of written option contracts open during the six months ended January 31,
     2018 was $(1,729).

     At January 31, 2018, the Fund had no outstanding written options.

K.   Purchased Options

     The Fund may purchase put and call options to seek increased total return.
     Purchased call and put options entitle the Fund to buy and sell a specified
     number of shares or units of a particular security, currency or index at a
     specified price at a specific date or within a specific period of time.
     Upon the purchase of a call or put option, the premium paid by the Fund is
     included in the Statements of Assets and Liabilities as an investment. All
     premiums are marked-to-market daily, and any unrealized gains or losses are
     recorded in the Fund's financial statements. As the purchaser of an index
     option, the Fund has the right to receive a cash payment equal to any
     depreciation in the value of the index below the strike price of the option
     (in the case of a put) or equal to any appreciation in the value of the
     index over the strike price of the option (in the case of a call) as of the
     valuation date of the option. Premiums paid for purchased call and put
     options which have expired are treated as realized losses on investments in
     the Statements of Operations. Upon the exercise or closing of a purchased
     put option, the premium is offset against the proceeds on the sale of the
     underlying security or financial instrument in order to determine the
     realized gain or loss on investments. Upon the


             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 41

<page>

     exercise or closing of a purchased call option, the premium is added to the
     cost of the security or financial instrument. The risk associated with
     purchasing options is limited to the premium originally paid.

     Purchased option contracts outstanding at period end, if any, are listed at
     the end of Fund's Schedule of Investments. The average value of purchased
     options open during the during the six months ended January 31, 2018 was
     $11,286.

     At January 31, 2018, the Fund had no outstanding purchased options.

L.   Credit Default Swap Contracts

     A credit default swap is a contract between a buyer of protection and a
     seller of protection against a pre-defined credit event on an underlying
     reference obligation, which may be a single security or a basket or index
     of securities. The Fund may sell or buy credit default swap contracts to
     seek to increase the Fund's income, or to attempt to hedge the risk of
     default on Fund securities. A credit default swap index is used to hedge
     risk or take a position on a basket of credit entities or indices.

     As a seller of protection, the Fund would be required to pay the notional
     (or other agreed-upon) value of the referenced debt obligation to the
     counterparty in the event of a default by a U.S. or foreign corporate
     issuer of a debt obligation, which would likely result in a loss to the
     Fund. In return, the Fund would receive from the counterparty a periodic
     stream of payments during the term of the contract provided that no event
     of default occurred. The maximum exposure of loss to the seller would be
     the notional value of the credit default swaps outstanding. If no default
     occurs, the Fund would keep the stream of payments and would have no
     payment obligation. The Fund may also buy credit default swap contracts in
     order to hedge against the risk of default of debt securities, in which
     case the Fund would function as the counterparty referenced above.

     As a buyer of protection, the Fund makes an upfront or periodic payment to
     the protection seller in exchange for the rights to receive a contingent
     payment. An upfront payment made by the Fund, as the protection buyer, is
     recorded as an asset in the Statements of Assets and Liabilities. Periodic
     payments received or paid by the Fund are recorded as realized gains or
     losses in the Statements of Operations.

     Credit default swap contracts are marked-to-market daily using valuations
     supplied by independent sources and the change in value, if any, is
     recorded within "swap contracts, at value" line item in the Statements of
     Assets and Liabilities. Payments received or made as a result of a credit
     event or upon

42 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>

     termination of the contract are recognized, net of the appropriate amount
     of the upfront payment, as realized gains or losses in the Statements of
     Operations.

     Credit default swap contracts involving the sale of protection may involve
     greater risks than if the Fund had invested in the referenced debt
     instrument directly. Credit default swap contracts are subject to general
     market risk, liquidity risk, counterparty risk and credit risk. If the Fund
     is a protection buyer and no credit event occurs, it will lose its
     investment. If the Fund is a protection seller and a credit event occurs,
     the value of the referenced debt instrument received by the Fund, together
     with the periodic payments received, may be less than the amount the Fund
     pays to the protection buyer, resulting in a loss to the Fund.

     Certain swap contracts that are cleared through a central clearinghouse are
     referred to as centrally cleared swaps. All payments made or received by
     the Fund are pursuant to a centrally cleared swap contracts with the
     central clearing party rather than the original counterparty. Upon entering
     into a centrally cleared swap contracts, the Fund is required to make an
     initial margin deposit, either in cash or in securities. The daily change
     in value on open centrally cleared contracts is recorded as variation
     margin on centrally cleared swaps on the Statements of Assets and
     Liabilities. Cash received from or paid to the broker related to previous
     margin movement, if any, is held in a segregated account at the broker and
     is recorded as either "Due from broker for swaps" or "Due to broker for
     swaps" in the Statement of Assets and Liabilities.

     The amount of cash deposited with the broker as collateral, if any, is
     recorded as "Swaps collateral" in the Statement of Assets and Liabilities.

     During six months ended January 31, 2018, the Fund had no open credit
     default swap contracts.

M.   Inflation Rate Swap Contracts

     The Fund may enter into inflation rate swap contracts to attempt to hedge
     against inflation. Pursuant to the inflation rate swap contract, the Fund
     negotiate with a counterparty to exchange a periodic stream of payments,
     based on a benchmark inflation index. One cash flow stream will typically
     be a floating rate payment linked to the specified inflation index while
     the other is typically a fixed interest rate.

     Inflation rate swap contracts are marked-to-market daily using valuations
     supplied by independent sources and the change in value, if any, is
     recorded within "swap contracts, at value" line item in the Statements of
     Assets and Liabilities. Inflation rate swaps are normally issued on a zero
     coupon basis

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 43

<page>

     where all payments compound during the life of the contract and are netted
     upon the termination or maturity of the contract. Final payments received
     or paid by the Fund are recorded as realized gains or losses in the
     Statements of Operations. Inflation rate swap contracts are subject to
     movements in interest rates.

     During six months ended January 31, 2018, the Fund had no open inflation
     rate swap contracts.

N.   Interest Rate Swap Contracts

     The Fund may enter into interest rate swaps to attempt to hedge against
     interest rate fluctuations or to enhance their income. Pursuant to the
     interest rate swap contract, the Fund negotiate with a counterparty to
     exchange a periodic stream of payments based on a benchmark interest rate.
     One cash flow stream will typically be a floating rate payment based upon
     the specified floating benchmark interest rate while the other is typically
     a fixed interest rate. Payment flows are usually netted against each other,
     with the difference being paid by one party to the other on a monthly
     basis.

     Periodic payments received or paid by the Fund are recorded as realized
     gains or losses in the Statements of Operations. Interest rate swap
     contracts are marked-to-market daily using valuations supplied by
     independent sources and the change in value, if any, is recorded within
     "swap contracts, at value" line item in the Statements of Assets and
     Liabilities. Interest rate swap contracts are subject to counterparty risk
     and movements in interest rates.

     Certain swap contracts that are cleared through a central clearinghouse are
     referred to as centrally cleared swaps. All payments made or received by
     the Fund are pursuant to a centrally cleared swap contract with the central
     clearing party rather than the original counterparty. Upon entering into a
     centrally cleared swap contract, the Fund is required to make an initial
     margin deposit, either in cash or in securities. The daily change in value
     on open centrally cleared swap contracts is recorded as variation margin on
     centrally cleared swaps on the Statement of Assets and Liabilities. Cash
     received from or paid to the broker related to previous margin movement, if
     any, is held in a segregated account at the broker and is recorded as
     either "Due from broker for swaps" or "Due to broker for swaps" in the
     Statement of Assets and Liabilities.

     The average value of interest rate swap contracts open during the six
     months ended January 31, 2018 was $(53,728).

     At January 31, 2018, the Fund had no open interest rate swap contract.

44 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>

2. Management Agreement

The Adviser manages the Fund's portfolios. Effective January 26, 2018, the Fund
does not pay a direct management fee to the Adviser. The Fund bears a pro rata
portion of the fees and expenses, including management fees, of each underlying
fund in which the Fund invests. The Fund invests primarily in funds managed by
the Adviser.

Prior to January 26, 2018, the Management fee for the Fund was calculated daily
at an annual rate equal to 0.13% of the Fund's average daily net assets up to
$2.5 billion; 0.11% of the Fund's average daily net assets over $2.5 billion up
to $4 billion; 0.10% of the Fund's average daily net assets over $4 billion up
to $5.5 billion; and 0.08% of the Fund's average daily net assets over $5.5
billion.

For the six months ended January 31, 2018, the effective management fee for Fund
was equivalent to 0.12% (Annualized) of the Fund's average daily net assets.
Fees waived and expenses reimbursed during the six months ended January 31, 2018
are reflected in the Statements of Operations.

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 Statements of Assets and Liabilities is
$790 payable to the Adviser at January 31, 2018.

The Adviser has contractually agreed to limit ordinary operating expenses to the
extent required to reduce fund expenses, other than underlying fund fees and
expenses to 0.70%, 1.45% and 0.90% of the average daily net assets attributable
to Class A, Class C and Class R shares, respectively. Effective January 26,
2018, the Adviser agreed to further limited the ordinary operating expenses of
Class R shares to 0.78% of the average daily net assets. These expense
limitations are in effect through December 1, 2019. There can be no assurance
that the Adviser, will extend the expense limitation agreement for a class of
shares beyond the date referred to above.

3. Transfer Agent

DST Asset Manager Solutions, Inc. serves as the transfer agent to the Fund at
negotiated rates. Transfer agent fees and payables shown on the Statement of
Operations and the Statement of Assets and Liabilities, respectively, include
sub-transfer agent expenses incurred through the Funds' omnibus relationship
contracts.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 45

<page>

In addition, the Fund reimbursed the transfer agent for out-of-pocket expenses
incurred by the transfer agent related to shareowner communications activities,
such as proxy and statement mailings, outgoing phone calls. For the six months
ended January 31, 2018, such out-of-pocket expenses by class of shares were as
follows:



---------------------------------
Shareowner Communications
---------------------------------
                       
Class A                   $16,153
Class C                     4,383
Class R                        31
Class Y                        33
---------------------------------
 Total                    $20,600
---------------------------------


4. Distribution and Service Plans

The Fund has adopted a Distribution Plan (the Plan) pursuant to Rule 12b-1 of
the Investment Company Act of 1940 with respect to Class A and Class C shares.
Pursuant to the Plan, Fund the Distributor, 0.25% of the Fund's average daily
net assets attributable to Class A shares as compensation for personal services
and/or account maintenance services or distribution services with respect to
Class A shares. Pursuant to the Plan, the Fund also pays the Distributor, 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 Statements of Assets and Liabilities is $19,392 in
distribution fees payable to the Distributor, at January 31, 2018.

The Fund also has adopted a separate service plan for Class R shares (Service
Plan). The Service Plan authorizes the Fund to pay securities dealers, plan
administrators or other service organizations that agree to provide certain
services to retirement plans or plan participants holding shares of the Fund a
distribution fee of up to 0.50% of the Fund's average daily net assets
attributable to Class R shares held by such plans.

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 CDSCs are paid to the
Distributor.

46 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>

For the six months ended January 31, 2018, CDSCs in the amount of $41,967 were
paid to the Distributor.

5. Assets and Liabilities Offsetting

The Fund has entered into an International Swaps and Derivatives Association,
Inc. Master Agreement ("ISDA Master Agreement") or similar agreement with
substantially all their derivative counterparties. An ISDA Master Agreement is a
bilateral agreement between the Fund and a counterparty that governs the trading
of certain OTC derivatives and typically contains, among other things, close-out
and set-off provisions which apply upon the occurrence of event of a default
and/or termination event as defined under the relevant ISDA Master Agreement.
The ISDA Master Agreement may also give a party the right to terminate all
transactions traded under such agreement if, among other things, there is
deterioration in the credit quality of the other party. Upon an event of default
or a termination of the ISDA Master Agreement, the non-defaulting party has the
right to close out all transactions under such agreement and to net amounts owed
under each transaction to determine one net amount payable by one party to the
other. The right to close out and net payments across all transactions under the
ISDA Master Agreement could result in a reduction of the Fund's credit risk to
their counterparty equal to any amounts payable by the Fund under the applicable
transactions, if any. However, the Fund's right to setoff may be restricted or
prohibited by the bankruptcy or insolvency laws of the particular jurisdiction
to which a specific ISDA counterparty is subject.

The collateral requirements for derivatives transactions under an ISDA Master
Agreement are governed by a credit support annex to the ISDA Master Agreement.
Collateral requirements are generally determined at the close of business each
day and are typically based on changes in market values for each transaction
under an ISDA Master Agreement and netted into one amount for such agreement.
Generally, the amount of collateral due from or to a counterparty is subject to
threshold (a "minimum transfer amount") before a transfer is required, which may
vary by counterparty. Collaterals pledged for the benefit of the Fund and/or
counterparty are held in segregated accounts by the Fund's custodian and cannot
be sold, re-pledged, assigned or otherwise used while pledged. Cash that has
been segregated to cover the Fund's collateral obligations, if any, will be
reported separately in the Statements of Assets and Liabilities as "swap
collateral". Securities pledged by the Fund as collateral, if any, are
identified as such in the Schedules of Investments.

At January 31, 2018, the Fund had no financial instruments subject to master
netting agreements.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 47

<page>

6. Additional Disclosures about Derivative Instruments and Hedging Activities

The Fund's use of derivatives may enhance or mitigate the Fund's exposure to the
following risks:

Interest rate risk relates to the fluctuations in the value of interest-bearing
securities due to changes in the prevailing levels of market interest rates.

Credit risk relates to the ability of the issuer of a financial instrument to
make further principal or interest payments on an obligation or commitment that
it has to the Fund.

Foreign exchange rate risk relates to fluctuations in the value of an asset or
liability due to changes in currency exchange rates.

Equity risk relates to the fluctuations in the value of financial instruments as
a result of changes in market prices (other than those arising from interest
rate risk or foreign exchange risk), whether caused by factors specific to an
individual investment, its issuer, or all factors affecting all instruments
traded in a market or market segment.

Commodity risk relates to the risk that the value of a commodity or commodity
index will fluctuate based on increases or decreases in the commodities market
and factors specific to a particular industry or commodity.

At January 31, 2018, the Fund had no open derivative instruments.

The effect of derivative instruments (not considered to be hedging instruments
for accounting disclosure purposes) on the Statement of Operations by risk
exposure at January 31, 2018 was as follows:



Statement of Operations
                                                                         
--------------------------------------------------------------------------------------------------
                                                         Foreign
                             Interest        Credit      Exchange         Equity        Commodity
                             Rate Risk       Risk        Risk             Risk          Risk
--------------------------------------------------------------------------------------------------
Net realized gain (loss):
 Futures contracts           $   (81,062)    $  --       $       --       $ 40,543      $  --
 Swap contracts                  (92,107)       --               --             --         --
 Written options                      --        --               --          9,940         --
 Forward foreign
  currency contracts                  --        --         (833,464)            --         --

--------------------------------------------------------------------------------------------------
 Total Value                 $  (173,169)    $  --       $ (833,464)      $ 50,483      $  --
--------------------------------------------------------------------------------------------------
Change in net
 unrealized appreciation
 (depreciation) on:
 Futures contracts           $   (72,638)    $  --       $       --       $ 95,437      $  --
 Swap contracts                   86,792        --               --             --         --
 Forward foreign
  currency contracts                  --        --          503,032             --         --
--------------------------------------------------------------------------------------------------
 Total Value                 $    14,154     $  --       $  503,032       $ 95,437      $  --
--------------------------------------------------------------------------------------------------


48 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>
7. Transactions in Underlying Funds

An affiliated issuer may be considered one in which a Fund owns 5% or more of
the outstanding voting securities, or a company which is under common control.
For the purposes of this report, Fund assumes the following to be affiliated
issuers:



                                                                        
-----------------------------------------------------------------------------------------------
                                    Beginning     Acquisitions    Dispositions      Ending
Underlying Funds (Affiliated)       Shares        Shares          Shares            Shares
-----------------------------------------------------------------------------------------------
Pioneer Bond Fund Class K           1,505,215        3,464,246         (93,086)      4,876,375
Pioneer Core Equity Fund Class Y      195,351        1,021,087              --       1,216,438
Pioneer Disciplined Value Fund
 Class Y                              491,134        1,749,215          (9,570)      2,230,779
Pioneer Dynamic Credit Fund
 Class Y                              491,341               --         (25,851)        465,490
Pioneer Flexible Opportunity
 Fund Class Y                              --          732,218              --         732,218
Pioneer Fund Class Y                  130,055          642,701              --         772,756
Pioneer Fundamental Growth
 Fund Class K                         173,510          988,888              --       1,162,398
Pioneer Global Equity Fund
 Class K                            1,078,851        2,506,740          (9,842)      3,575,749
Pioneer Global High Yield
 Fund Class Y                         312,079           17,231              --         329,310
Pioneer High Yield Fund Class Y             1           12,638              --          12,639
Pioneer International Equity
  Fund Class Y                      1,172,294        2,358,211         (34,337)      3,496,168
Pioneer Mid Cap Value Fund
 Class K                              228,181          901,902          (6,566)      1,123,517
Pioneer Multi-Asset Income
 Fund Class K                              --        1,711,491              --       1,711,491
Pioneer Multi-Asset Ultrashort
 Income Fund Class K                       --        2,006,000              --       2,006,000
Pioneer Strategic Income
 Fund Class K                       2,036,411        2,853,549              --       4,889,960
-----------------------------------------------------------------------------------------------


8. Reorganization Information

On January 26, 2018 ("Closing Date"), each of Pioneer Solutions --Conservative
Fund ("Conservative Fund") and Pioneer Solutions -- Growth Fund ("Growth Fund")
was reorganized into Balanced Fund. The purpose of these transactions was to
combine three funds (managed by the Adviser) with similar investment objectives
and strategies.

These tax-free reorganizations were accomplished by exchanging the assets and
liabilities of each of Conservative Fund and Growth Fund for shares of Balanced
Fund. Shareowners holding Class A, Class C, Class R and Class Y shares of
Conservative Fund or Growth Fund received Class A, Class C, Class R and Class
Y shares of Balanced Fund, respectively, in the applicable reorganization. The
investment portfolios of Conservative Fund and Growth

     Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 49

<page>
Fund, with aggregate values of $54,077,862 and $300,758,764, respectively and
identified costs of $51,906,012 and $249,818,545, respectively at January 26,
2018, were the principal assets acquired by Balanced Fund.

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

The following charts show the details of the reorganizations as of the Closing
Date:



                                                                        
--------------------------------------------------------------------------------------------------------
                   Conservative Fund    Growth Fund          Balanced Fund         Balanced Fund
                   (Pre-Reorganization) (Pre-Reorganization) (Pre-Reorganization)  (Post-Reorganization)
--------------------------------------------------------------------------------------------------------
Net Assets
 Class A             $42,512,512          $258,713,220         $120,717,585         $421,943,317
 Class C              13,374,507            68,899,528           49,202,929          131,476,964
 Class R                 122,830                44,902               92,342              260,074
 Class Y                 282,732             1,036,332              665,782             1,984,846
-------------------------------------------------------------------------------------------------------
Total Net Assets     $56,292,581          $328,693,982         $170,678,638         $555,665,201
-------------------------------------------------------------------------------------------------------
Shares Outstanding
 Class A               3,963,344            18,570,366            9,550,718           32,084,428
 Class C               1,285,133             5,269,196            4,229,483           10,783,812
 Class R                  11,469                 3,247                7,345               22,061
 Class Y                  28,036                72,720               51,992              152,748




                                                                        
--------------------------------------------------------------------------------------------------------
                                                             Shares Issued          Shares Issued
                    Exchange Ratio      Exchange Ratio       in Reorganization of   in Reorganization of
                    Conservative Fund   Growth Fund          Conservative Fund      Growth Fund
--------------------------------------------------------------------------------------------------------
Class A             0.8486              1.1022               3,363,332              20,467,818
Class C             0.8948              1.1243               1,150,001               5,924,293
Class R             0.8520              1.1001                   9,772                  3,572
Class Y             0.7872              1.1125                  22,071                 80,900

                                                             Unrealized              Accumulated
                                                             Appreciation            Gain (Loss) on
                                                             on Closing Date         Closing Date
Balanced                                                     $22,087,752             $(5,549,376)
Conservative                                                 $ 2,171,849             $(1,460,953)
Growth                                                       $50,940,894             $ 9,588,903


50 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18


<page>
Assuming the reorganizations had been completed on August 1, 2017, the
beginning of the Fund's current fiscal period, the pro forma results of
operations for the six months ended January 31, 2018, are as follows:



                                                     
--------------------------------------------------------------------
Net Investment Income (Loss)                            $22,983,323
Net Realized and Unrealized Gains                        76,618,061
--------------------------------------------------------------------
Change in Net Assets Resulting from Operations          $99,601,384
--------------------------------------------------------------------


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

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 51

<page>
ADDITIONAL INFORMATION

Change in Independent Registered Public Accounting Firm

Prior to July 3, 2017 Pioneer Investment Management, Inc. (the "Adviser"), the
Fund's investment adviser, was an indirect, wholly owned subsidiary of
UniCredit S.p.A. ("UniCredit"). On that date, UniCredit completed the sale of
its Pioneer Investments business, which includes the Adviser, to Amundi (the
"Transaction"). As a result of the Transaction, the Adviser became an indirect,
wholly-owned subsidiary of Amundi. Amundi is controlled by Credit Agricole S.A.
Amundi is headquartered in Paris, France, and, as of September 30, 2016, had
more than $1.1 trillion in assets under management worldwide.

Deloitte & Touche LLP ("D&T"), the Fund's previous independent registered
public accounting firm, informed the Audit Committee and the Board that it
would no longer be independent with respect to the Fund upon the completion of
the Transaction as a result of certain services being provided to Amundi and
Credit Agricole, and, accordingly, that it intended to resign as the Fund's
independent registered public accounting firm upon the completion of the
Transaction. D&T's resignation was effective on July 3, 2017, when the
Transaction was completed.

During the periods as to which D&T has served as the Fund's independent
registered public accounting firm, including the Fund's two most recent fiscal
years preceding the fiscal year ended July 31, 2017, D&T's reports on the
Fund's financial statements 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
D&T on any matter of accounting principles or practices, financial statement
disclosure, or auditing scope or procedure, which, if not resolved to the
satisfaction of D&T, would have caused D&T 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.

Effective immediately following the completion of the Transaction on July 3,
2017, the Board, acting upon the recommendation of the Audit Committee, engaged
a new independent registered public accounting firm, Ernst & Young LLP ("EY"),
for the Fund's fiscal year ended July 31, 2017.

Prior to its engagement, EY had advised the Fund's Audit Committee that EY had
identified the following matters, in each case relating to services rendered by
other member firms of Ernst & Young Global Limited, all of which are located
outside the United States, to UniCredit and certain of its subsidiaries

52 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
during the period commencing July 1, 2016, that it determined to be
inconsistent with the auditor independence rules set forth by the Securities
and Exchange Commission ("SEC"): (a) project management support services to
UniCredit in the Czech Republic, Germany, Italy, Serbia and Slovenia in
relation to twenty-two projects, that were determined to be inconsistent with
Rule 2-01(c)(4)(vi) of Regulation S-X (management functions); (b) two
engagements for UniCredit in Italy where fees were contingent/success based and
that were determined to be inconsistent with Rule 2-01(c)(5) of Regulation S-X
(contingent fees); (c) four engagements where legal and expert services were
provided to UniCredit in the Czech Republic and Germany, and twenty engagements
where the legal advisory services were provided to UniCredit in Austria, Czech
Republic, Italy and Poland, that were determined to be inconsistent with Rule
2-01(c)(4)(ix) and (x) of Regulation S-X (legal and expert services); and (d)
two engagements for UniCredit in Italy involving assistance in the sale of
certain assets, that were determined to be inconsistent with Rule
2-01(c)(4)(viii) of Regulation S-X (broker-dealer, investment advisor or
investment banking services). None of the foregoing services involved the Fund,
any of the other funds in the Pioneer Family of Funds or any other Pioneer
entity sold by UniCredit in the Transaction.

EY advised the Audit Committee that it had considered the matters described
above and had concluded that such matters would not impair EY's ability to
exercise objective and impartial judgment in connection with the audits of the
financial statements of the Fund under the SEC and Public Company Accounting
Oversight Board independence rules, and that a reasonable investor with
knowledge of all relevant facts and circumstances would reach the same
conclusion. Management and the Audit Committee considered these matters and
discussed the matters with EY and, based upon EY's description of the matters
and statements made by EY, Management and the Audit Committee believe that EY
will be capable of exercising objective and impartial judgment in connection
with the audits of the financial statements of the Fund, and Management further
believes that a reasonable investor with knowledge of all relevant facts and
circumstances would reach the same conclusion.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 53

<page>
Trustees, Officers and Service Providers



                             
Trustees                        Officers
Thomas J. Perna, Chairman       Lisa M. Jones, President and
David R. Bock                     Chief Executive Officer
Benjamin M. Friedman            Mark E. Bradley, Treasurer and
Margaret B.W. Graham              Chief Financial Officer
Lisa M. Jones                   Christopher J. Kelley, Secretary and
Lorraine H. Monchak               Chief Legal Officer
Marguerite A. Piret
Fred J. Ricciardi
Kenneth J. Taubes


Investment Adviser and Administrator
Amundi Pioneer Asset Management, Inc.

Custodian and Sub-Administrator
Brown Brothers Harriman & Co.

Principal Underwriter
Amundi Pioneer Distributor, Inc.

Legal Counsel
Morgan, Lewis & Bockius LLP

Shareowner Services and Transfer Agent
DST Asset Manager Solutions, 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 www.amundipioneer.com. This information is also available on the
Securities and Exchange Commission's web site at www.sec.gov.

54 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
                          This page is for your notes.

     Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 55
<page>
                          This page is for your notes.

56 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
                          This page is for your notes.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 57
<page>
                          This page is for your notes.

58 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
                          This page is for your notes.

             Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18 59
<page>
                          This page is for your notes.

60 Pioneer Solutions -- Balanced Fund | Semiannual Report | 1/31/18
<page>
How to Contact Amundi 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

FactFoneSM for automated fund yields, prices,
account information and transactions                              1-800-225-4321

Retirement plans information                                      1-800-622-0176


Write to us:
--------------------------------------------------------------------------------
Amundi Pioneer
P.O. Box 55014
Boston, Massachusetts 02205-5014

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

Our internet e-mail address                us.askamundipioneer@amundipioneer.com
(for general questions about Amundi Pioneer only)

Visit our web site: www.amundipioneer.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.
<page>


Amundi Pioneer Asset Management, Inc.
60 State Street
Boston, MA 02109
www.amundipioneer. com

Securities offered through Amundi Pioneer Distributor, Inc.
60 State Street, Boston, MA 02109
Underwriter of Pioneer Mutual Funds, Member SIPC
[C] 2018 Amundi Pioneer Asset Management 19016-12-0318


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.

N/A

(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.

N/A


(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.

N/A

(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.

N/A

(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 Amudi Pioneer Asset Management, Inc, 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.

N/A


(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.

N/A

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

ITEM 5. AUDIT COMMITTEE OF LISTED REGISTRANTS

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

(a) If the registrant is a closed-end management investment company,
provide the following dollar amounts of income and compensation related
to the securities lending activities of the registrant during its most
recent fiscal year:

N/A

(1) Gross income from securities lending activities;

N/A

(2) All fees and/or compensation for each of the following securities
lending activities and related services: any share of revenue generated
by the securities lending program paid to the securities lending agent(s)
(revenue split); fees paid for cash collateral management services
(including fees deducted from a pooled cash collateral reinvestment
vehicle) that are not included in the revenue split; administrative
fees that are not included in the revenue split; fees for
indemnification that are not included in the revenue split; rebates
paid to borrowers; and any other fees relating to the securities lending
program that are not included in the revenue split, including a description
of those other fees;

N/A

(3) The aggregate fees/compensation disclosed pursuant to paragraph (2); and

N/A

(4) Net income from securities lending activities (i.e., the dollar amount in
paragraph (1) minus the dollar amount in paragraph (3)).

If a fee for a service is included in the revenue split, state that the fee
is included in the revenue split.

N/A

(b) If the registrant is a closed-end management investment company, describe
the services provided to the registrant by the securities lending agent in
the registrants most recent fiscal year.

N/A


ITEM 13. 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 Asset Allocation Trust


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

Date March 27, 2018


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 March 27, 2018


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

Date March 27, 2018

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