More About the Pioneer Four^SM

Pioneer Fund

Has Outpaced the S&P 500 Index Since Inception in 1928¹

• Fourth oldest U.S. mutual fund, founded in 1928
• Portfolio manager since 1986, John Carey is only the 4th manager in the Fund's 75-year history
• A large-cap value fund with historically low portfolio turnover, 7% as of 12/31/02*
• Actively managed, "bottom-up" value investment approach
• Suitable as the cornerstone of an asset allocation program

Click here for the fund's performance, including standardized returns at the public offering price.

For more information, including charges and expenses, click here for the fund's prospectus.

Pioneer High Yield Fund
OVERALL MORNINGSTAR RATING^TM
as of 9/30/03
(out of 322 high yield bond funds)

High Yield Market Currently Offers Wide Spreads over U.S.Treasuries²

• Ranked #1 by Lipper among 194 high current income funds since inception (2/12/98), #1 among 235 for the five-year period, #8 among 322 for the three-year period, and #49 among 385 for the one year period as of 9/30/03^†
• Total return fund with high current income potential
• Research intensive credit and issue selection process
• Focuses on fundamentally sound companies with adequate liquidity in strong and growing industries

Click here for the fund's performance, including standardized returns at the public offering price.

For more information, including charges and expenses, click here for the fund's prospectus.

Pioneer High Yield Fund invests in below investment grade securities, which may be more volatile than investment grade securities.

Pioneer Mid Cap Value Fund

Mid-Cap Value Stocks Outpaced Mid-Cap Growth Stocks
1/1/86-9/30/03³

• Managed by Rod Wright since 1997
• A style-pure mid-cap value fund investing in medium sized companies offering the growth potential of small companies and the relative stability of larger ones
• Uses fundamental research in seeking quality companies at attractive valuations with a catalyst for potential appreciation

Click here for the fund's performance, including standardized returns at the public offering price.

For more information, including charges and expenses, click here for the fund's prospectus.

Mid-cap stocks may be more volatile and less liquid than stocks of larger companies.

Pioneer Small Cap Value Fund
OVERALL MORNINGSTAR RATING^TM
as of 9/30/03
(out of 273 small blend funds)

Small-Cap Value Stocks Outpaced Small-Cap Growth Stocks
1/1/79-9/30/03⁴

• Targets companies that have been overlooked, are trading at significant discounts from their all time highs, and have a catalyst for future growth prospects
• Original research – Pioneer's dedicated small cap team relies heavily on research generated by frequent face-to-face meetings with company managements
• Managed by a team of experienced portfolio managers all of whom have contributed to the fund since inception in 1997

Click here for the fund's performance, including standardized returns at the public offering price.

For more information, including charges and expenses, click here for the fund's prospectus.

Small-cap stocks may be more volatile and less liquid than stocks of larger companies.

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Learn more . . .
For more information about any Pioneer fund, contact your financial advisor. This material must be preceded or accompanied by a copy of the prospectus for Pioneer Fund, Pioneer High Yield Fund, Pioneer Mid Cap Value Fund and Pioneer Small Cap Value Fund. The prospectuses contain more information, including charges and expenses. Investors should read them carefully before investing or sending money.

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Past performance is no guarantee of future results.
Assumes reinvestment of all distributions at net asset value. Return and principal value will fluctuate so shares, when redeemed, may be worth more or less than their original cost. POP performance reflects deduction of maximum 5.75% and 4.50% sales charge for equity funds and Pioneer High Yield Fund, respectively. Current performance may be lower due to market volatility. Visit www.pioneerfunds.com or call 1-800-225-6292 for monthly updates. Class B and C shares are also available.

1 Chart source: Towers Data. Investment period 3/1/28-9/30/03. Fund performance assumes reinvestment of all distributions at net asset value. Results reflect maximum sales charge of 5.75%. The S&P 500 Index is an unmanaged barometer of U.S. stock market performance. It is not possible to invest directly in an index. Chart prepared by Pioneer for illustrative purposes only. Does not reflect actual investor results.

2 Chart source: Pioneer Research. Merrill Lynch High Yield Master II Index and Merrill Lynch U.S. Current 10-Year Treasury Index are unmanaged representations of the performance of non-investment-grade U.S. domestic bonds and U.S 10-Year Treasuries, respectively. It is not possible to invest directly in an index. Treasury securities are guaranteed as to the timely payment of interest and principal; high yield corporate bonds are not. Investments in lower rated bonds may be more volatile and less liquid than more highly rated bonds. Chart prepared by Pioneer.

3 Chart source: Pioneer Research. Assumes reinvestment of dividends. The Russell Midcap Value and Growth Indices are unmanaged representations of the performance of mid-cap value and mid-cap growth stocks, respectively. It is not possible to invest directly in an index. Chart prepared by Pioneer.

4 Chart source: Pioneer Research. Assumes reinvestment of all dividends. The Russell 2000 Value and Growth Indices are unmanaged representations of the performance of small-cap value and growth stocks, respectively. It is not possible to invest directly in an index. Chart prepared by Pioneer.

* Turnover will vary for different periods.

† Lipper rankings are based on total return for Class A shares and do not take sales charges into account, which would lower returns. Lipper Analytical Services, Inc. is an independent organization that compiles data on investment companies.

Morningstar proprietary ratings reflect risk-adjusted performance as of 9/30/03. For each fund with at least a three-year history, Morningstar calculates a Morningstar Rating^TM based on a Morningstar Risk-Adjusted Return measure that accounts for variation in a fund's monthly performance (including the effects of sales charges, loads, and redemption fees), placing more emphasis on downward variations and rewarding consistent performance. The top 10% of funds in each category receive 5 stars, the next 22.5% receive 4 stars, the next 35% receive 3 stars, the next 22.5% receive 2 stars and the bottom 10% receive 1 star. (Each share class is counted as a fraction of one fund within this scale and rated separately, which may cause slight variations in the distribution percentages.) The Overall Morningstar Rating for a fund is derived from a weighted average of the performance figures associated with its three-, five- and ten-year (if applicable) Morningstar Rating metrics. Pioneer High Yield Fund was rated against high yield bond funds for Class A shares only. The Fund earned a rating of 5 stars out of 322 and 235 funds for the three- and five- year periods respectively. Pioneer Small Cap Value Fund was rated exclusively against small blend funds for Class A shares only. The Fund earned a rating of 3 stars out of 273 and 4 stars out of 207 small blend funds for the three- and five- year periods respectively. Past performance is no guarantee of future results.

Pioneer Fund and Mid Cap Value Fund are subject to certain risks characteristic of overseas investing, including, but not limited to, currency fluctuations, social and economic instability, differing securities regulations and accounting standards, limited public information, possible changes in taxation and periods of illiquidity. Pioneer High Yield Fund invests in below-investment-grade securities, which may be more volatile and riskier than investment-grade securities. Mid-and small-cap stocks, may be more volatile and less liquid than stocks of larger companies.

Morningstar data contained herein: ©2003 Morningstar, Inc. All Rights Reserved. (1) is proprietary to Morningstar; (2) may not be copied or distributed and (3) is not warranted to be accurate, complete or timely. Morningstar is not responsible for any damages or losses arising from any use of this information and has not granted its consent to be considered or deemed an "expert" under the Securities Act of 1933.