Pioneer Fund - -------------------------------------------------------------------------------- Annual Report | December 31, 2008 - -------------------------------------------------------------------------------- Ticker Symbols: Class A PIODX Class B PBODX Class C PCODX Class R PIORX Class Y PYODX Class Z PIOZX [LOGO]PIONEER Investments(R) visit us: pioneerinvestments.com Table of Contents Letter to Shareowners 2 Portfolio Management Discussion 4 Portfolio Summary 8 Prices and Distributions 9 Performance Update 10 Comparing Ongoing Fund Expenses 16 Schedule of Investments 18 Financial Statements 27 Notes to Financial Statements 37 Report of Independent Registered Public Accounting Firm 44 Trustees, Officers and Service Providers 45 Pioneer Fund | Annual Report | 12/31/08 1 President's Letter Dear Shareowner, Stock and bond markets around the globe this year have experienced one of their most tumultuous periods in history. Investors have witnessed volatility of a magnitude that many have never before seen. Distance often provides the best vantage point for perspective. Still, we believe that the benefits of basic investment principles that have stood the test of time -- even in the midst of market turmoil -- cannot be underestimated. First, invest for the long term. The founder of Pioneer Investments, Philip L. Carret, began his investment career during the 1920s. One lesson he learned is that while great prosperity affords an advantageous time for selling stocks, extreme economic slumps can create opportunities for purchase. Indeed, many of our portfolio managers, who follow the value-conscious investing approach of our founder, are looking at recent market conditions as an opportunity to buy companies whose shares we believe have been unjustifiably beaten down by indiscriminate selling, but that we have identified as having strong prospects over time. While investors may be facing a sustained market downturn, we continue to believe that patience, along with staying invested in the market, are important considerations for long-term investors. A second principle is to stay diversified across different types of investments. The global scope of the current market weakness poses challenges for this basic investment axiom. But the turbulence makes now a good time to reassess your portfolio and make sure that your investments continue to meet your needs. We believe you should work closely with your financial advisor to find the mix of stocks, bonds and money market assets that is best aligned to your particular risk tolerance and investment objective. As the investment markets sort through the continuing crisis in the financial industry, we are staying focused on the fundamentals and risk management. With more than 80 years of experience behind us, we have learned how to navigate turbulent markets. At Pioneer Investments, risk management has always been a critical part of our culture -- not just during periods of extraordinary volatility. Our investment process is based on fundamental research, quantitative analysis and active portfolio management. This three-pillared process, which we apply to each of our portfolios, is supported by an integrated team approach and is designed to carefully balance risk and reward. While we 2 Pioneer Fund | Annual Report | 12/31/08 see potential chances for making money in many corners of the market, it takes research and experience to separate solid investment opportunities from speculation. We invite you to learn more about Pioneer and our time-tested approach to investing by consulting with your financial advisor or visiting us online at www.pioneerinvestments.com. Thank you for investing with Pioneer. Respectfully, /s/Daniel K. Kingsbury Daniel K. Kingsbury President and CEO Pioneer Investment Management USA, Inc. Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund's historical or future performance are statements of the opinion of Fund management as of the date of this report. These statements should not be relied upon for any other purposes. Past performance is no guarantee of future results, and there is no guarantee that market forecasts discussed will be realized. Pioneer Fund | Annual Report | 12/31/08 3 Portfolio Management Discussion | 12/31/08 The year 2008 was one of the worst on record for investors. The American banking system all but collapsed, industrial activity slowed markedly, and unemployment rose significantly. Business and consumer confidence dropped. Companies both large and small ran into trouble, and some ceased to exist or were absorbed into other companies, occasionally with U.S. government prodding. The fall Presidential election turned largely into a debate over what to do next as both major candidates seemed unable to offer any reassurance that everything could be put right quickly. As the United States settled into recession, many other countries around the world also saw their economies weaken. When the year ended, the world seemed to be confronting the first truly global slowdown in quite some time. In the following interview, John Carey, portfolio manager of the Pioneer Fund, discusses the market environment during the 12 months ended December 31, 2008, and how it affected the Fund's performance. Q How did the Fund fare through the end of 2008, one of the most tumultuous years in the history of equity markets? A The performance of the Pioneer Fund suffered during the downturn, though the results were somewhat better than those of the overall market and competing funds. For the 12 months ended December 31, 2008, Class A shares of the Fund returned -34.38% at net asset value, versus the -36.99% return for the benchmark Standard & Poor's 500 Index (the S&P 500), and the -37.23% average return for the 851 funds in Lipper Analytical Services' large-cap core category. Most of the losses came in the second half of the year: for the six months ended December 31, 2008, Class A shares of the Fund returned -27.31% at net asset value, versus returns of -28.48% for the S & P 500 and -29.22% for the average fund in the Lipper category. During the year as a whole and also during the second half of 2008, both our stock selection and our sector allocations provided the performance advantage over the Fund's competitors and the benchmark. Of course we realize that relative performance is small consolation to our shareholders when the absolute performance numbers are so weak, but we take some satisfaction from having preserved just a bit more value than the majority of portfolios in our Lipper category. Q Please discuss the Fund's performance during the last six months of 2008. Specifically, which holdings and sector allocations had the greatest positive and negative effects on performance relative to the benchmark S&P 500 Index? 4 Pioneer Fund | Annual Report | 12/31/08 A The most important contributors to relative performance were the Fund's underweights and stock selections in the underperforming financials and energy sectors. While managing to avoid some of the worst stocks among the financials, including American International Group and Citigroup, the Fund also had two of the few stocks in that sector that performed comparatively well, Chubb and SAFECO. In energy, the Fund's light investment in the swooning oil-services industry was the key factor. Negative factors in performance for the Fund included our overweight and stock selections in the underperforming materials sector and our stock selections in the consumer discretionary and staples sectors. After doing well earlier in the year, the metals and mining stocks within materials plummeted in the second half as commodities prices fell sharply. In the consumer sectors, the Fund was hurt by not owning some of the stocks that held up particularly well in the economic downturn, including Procter & Gamble and Wal-Mart Stores. Q Energy prices soared to historic highs during the year, and then plunged later in the year as global economic growth slowed and consumers cut back on energy usage. How is the Fund positioned in energy and other commodities, and what is your view of the commodities over the next year? A At December 31, 2008, the Fund was still underweight the energy sector, but remained overweight the materials sector. If one takes the two natural- resources sectors together, however, the Fund was only slightly underweight the S&P 500 allocation to the sectors. The Fund was underweight the energy sector from the beginning of the year because of concern over the rising costs for the companies and skepticism of the high oil prices. Sure enough, oil prices came down, and profits for the companies were squeezed. We did make new investments in energy in the second half, believing that the sharply lower share prices for many of the companies no longer reflected the positive longer-term prospects. Marathon Oil is a leading refiner of petroleum products and also has international exploration-and-production operations. Schlumberger is perhaps the leading international oil-services company. But overall we are still cautious on energy. With respect to materials, we were, in retrospect, much too sanguine about the potential for metals. The economic slowdown hit the miners very hard, and the performance of the stocks later in the year was even more dismal than that of the energy names. The longer-term picture appears bright, with growing demand for metals from industrializing parts of the world. In the near term, though, it will all be about survival, particularly in view of the leveraged balance sheets of some of the miners that made acquisitions near peak prices. Pioneer Fund | Annual Report | 12/31/08 5 Q Oftentimes a weak stock market presents investment opportunities. Did you find some over the second half of the reporting period, and, overall, can you discuss changes you made to the Fund? A As we look at the stock market, we see many stocks selling at lower prices than we have seen in a long time. The sell-off has been, we think, quite undiscriminating, as investors have seemed just to want to "get out of the market," no matter what the price. So, yes, we have seen what we regarded as bargains. At the same time, we have also sold stocks of companies we did not think were as well positioned for the difficult times in which we find ourselves. Overall, we added eight names to the Fund during the six months ended December 31, 2008, and eliminated thirteen. With respect to initiated positions, we have already mentioned Marathon Oil and Schlumberger. Monsanto is a leading producer of seeds, pesticides, and herbicides, with a premier reputation in the agricultural market. Stryker makes surgical and medical devices and equipment and is most noted for its orthopedic implants, including artificial hips, knees, and shoulders. Aflac is a supplemental insurance provider with a particularly strong market presence in Japan. International Business Machines is the most diversified technology company, with leading businesses in computer software, hardware, and services. First Energy and PPL are public utilities. What all the stocks had in common was a lower share price at our time of purchase than our appraisal of underlying, long-term value. With respect to sales from the Fund, good gains were realized on the stocks of two companies that were acquired at premium prices by other companies: SAFECO, which was bought by fellow insurance company Liberty Mutual; and Barr Pharmaceuticals, which was taken over by Teva Pharmaceuticals, also a Fund holding. The acquisition of Barr was in exchange for a combination of cash and Teva shares. Our other sales were made for a variety of reasons, including disappointment with growth prospects, concern for financial condition, and less attractive prospects than we had originally envisioned. That liquidation list comprised Ford Motor, Gannett, Zimmer, Banco Bilbao Vizcaya Argentaria (BBVA), Hartford Financial, MetLife, Microsoft, Corning, Motorola, Dell, and Sun Microsystems. Q A year like 2008 can cause even the most confident of investors to lose heart, and even some of the bluest of the blue-chip stocks took a beating over the last year. That said, what is your outlook for the coming year? A The biggest issue for investors currently is uncertainty over the length of the ongoing economic recession in the U.S. The spread of the recession overseas has also affected the ability of American companies to expand the exports on which so many of them have come to depend for growth. With respect to the public-policy responses to date, in the form of massive bail-outs and other "rescue packages," the jury is still out on whether they are likely to 6 Pioneer Fund | Annual Report | 12/31/08 help much. We do know that the programs are expensive, and there is concern among investors over the longer-range budgetary implications of what the outgoing administration has already done and the incoming administration is promising. For now, the Federal Reserve is much more focused on the economic contraction than on the more distant risk of inflation and so has pushed short-term interest rates down to very low, almost negligible levels. But that emphasis could change quickly if the economy does appear over the next few quarters to have regained its footing. Despite everything, however, we are of the opinion that this is a business cycle and not the spiral to oblivion, and that in due course, no matter whether the government responses are effective or not, the economy will improve. We continue to have great faith in the resilience of our country and its people. We have also observed that investments made during past periods of economic distress and extreme uncertainty, at the bargain-basement prices often prevailing, have often worked out well when held for the long term by patient shareholders. Certainly we are excited by the low prices of many stocks today. Will this time be different, and will investors instead be disappointed? We are proceeding under the assumption that that will not be the case, but we must emphasize the risks and the unknown time horizon. Thank you for your support. Please refer to the Schedule of Investments on pages 18-26 for a full listing of Fund securities. At times, the Fund's investments may represent industries or industry sectors that are interrelated or have common risks, making it more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors. Past performance is no guarantee of future results, and there is no guarantee that market forecasts discussed will be realized. Any information in this shareholder report regarding market or economic trends or the factors influencing the Fund's historical or future performance are statements of the opinion of Fund management as of the date of this report. These opinions should not be relied upon for any other purposes. Pioneer Fund | Annual Report | 12/31/08 7 Portfolio Summary | 12/31/08 Portfolio Diversification - -------------------------------------------------------------------------------- (As a percentage of total investment portfolio) [THE FOLLOWING DATA IS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL.] U.S. Common Stocks 83.6% Temporary Cash Investments 9.9% Depositary Receipts for International Stocks 4.2% International Common Stocks 2.3% Sector Distribution - -------------------------------------------------------------------------------- (As a percentage of equity holdings) [THE FOLLOWING DATA IS REPRESENTED AS A PIE CHART IN THE PRINTED MATERIAL.] Industrials 16.6% Consumer Staples 16.6% Health Care 14.7% Information Technology 11.4% Consumer Discretionary 11.2% Financials 9.7% Energy 9.7% Materials 5.4% Telecommunication Services 2.6% Utilities 2.1% 10 Largest Holdings - -------------------------------------------------------------------------------- (As a percentage of equity holdings)* 1. Chevron Corp. 4.02% 2. Norfolk Southern Corp. 3.06 3. John Wiley & Sons, Inc. 2.70 4. Chubb Corp. 2.60 5. Becton, Dickinson & Co. 2.29 6. Hewlett-Packard Co. 2.15 7. Colgate-Palmolive Co. 2.13 8. PepsiCo, Inc. 1.96 9. United Technologies Corp. 1.94 10. PACCAR, Inc. 1.86 * This list excludes temporary cash investments and derivative instruments. The portfolio is actively managed, and current holdings may be different. The holdings listed should not be considered recommendations to buy or sell any security listed. 8 Pioneer Fund | Annual Report | 12/31/08 Prices and Distributions | 12/31/08 Net Asset Value per Share - -------------------------------------------------------------------------------- Class 12/31/08 12/31/07 A $ 29.13 $ 46.32 - -------------------------------------------------------------------------------- B $ 28.43 $ 45.11 - -------------------------------------------------------------------------------- C $ 27.96 $ 44.55 - -------------------------------------------------------------------------------- R $ 29.17 $ 46.37 - -------------------------------------------------------------------------------- Y $ 29.22 $ 46.45 - -------------------------------------------------------------------------------- Z $ 29.20 $ 46.41 - -------------------------------------------------------------------------------- Distributions per Share: 1/1/08-12/31/08 - -------------------------------------------------------------------------------- Net Investment Short-Term Long-Term Class Income Capital Gains Capital Gains A $ 0.4467 $ -- $ 0.8550 - -------------------------------------------------------------------------------- B $ -- $ -- $ 0.8550 - -------------------------------------------------------------------------------- C $ 0.1575 $ -- $ 0.8550 - -------------------------------------------------------------------------------- R $ 0.3905 $ -- $ 0.8550 - -------------------------------------------------------------------------------- Y $ 0.6254 $ -- $ 0.8550 - -------------------------------------------------------------------------------- Z $ 0.6190 $ -- $ 0.8550 - -------------------------------------------------------------------------------- Index Definitions - -------------------------------------------------------------------------------- The Standard & Poor's 500 (S&P) Index is a commonly used measure of the broad U.S. stock market. Index returns assume reinvestment of dividends and, unlike Fund returns, do not reflect any fees, expenses or sales charges. You cannot invest directly in an index. The index defined here pertains to the "Value of $10,000 Investment" charts on pages 10-15. Pioneer Fund | Annual Report | 12/31/08 9 Performance Update | 12/31/08 Class A Shares Investment Returns - -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Pioneer Fund at public offering price, compared to that of the Standard & Poor's 500 Index. Average Annual Total Returns (As of December 31, 2008) - ------------------------------------------------------------------ Net Asset Public Offering Period Value (NAV) Price (POP) - ------------------------------------------------------------------ 10 Years -0.31% -0.89% 5 Years -1.03 -2.19 1 Year -34.38 -38.16 - ------------------------------------------------------------------ Expense Ratio (Per prospectus dated May 1, 2008) - ------------------------------------------------------------------ Gross Net - ------------------------------------------------------------------ 1.11% 1.11% - ------------------------------------------------------------------ [THE FOLLOWING DATA IS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL.] Value of $10,000 Investment Pioneer Standard & Poor's Fund 500 Index 12-98 $ 9,425 $10,000 $10,891 $12,103 12-00 $10,903 $11,002 $ 9,690 $ 9,695 12-02 $ 7,727 $ 7,553 $ 9,626 $ 9,719 12-04 $10,746 $10,775 $11,433 $11,304 12-06 $13,306 $13,088 $13,932 $13,807 12-08 $ 9,142 $ 8,699 Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. NAV results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. POP returns reflect deduction of maximum 5.75% sales charge. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 10 Pioneer Fund | Annual Report | 12/31/08 Performance Update | 12/31/08 Class B Shares Investment Returns - -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Pioneer Fund, compared to that of the Standard & Poor's 500 Index. Average Annual Total Returns (As of December 31, 2008) - --------------------------------------------------------------- If If Period Held Redeemed - --------------------------------------------------------------- 10 Years -1.18% -1.18% 5 Years -1.91 -1.91 1 Year -34.99 -37.51 - --------------------------------------------------------------- Expense Ratio (Per prospectus dated May 1, 2008) - --------------------------------------------------------------- Gross Net - --------------------------------------------------------------- 1.99% 1.99% - --------------------------------------------------------------- [THE FOLLOWING DATA IS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL.] Value of $10,000 Investment Pioneer Standard & Poor's Fund 500 Index 12-98 $10,000 $10,000 $11,455 $12,103 12-00 $11,368 $11,002 $10,018 $ 9,695 12-02 $ 7,919 $ 7,553 $ 9,775 $ 9,719 12-04 $10,818 $10,775 $11,402 $11,304 12-06 $13,161 $13,088 $13,656 $13,807 12-08 $ 8,878 $ 8,699 Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. 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. "If Held" results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. "If Redeemed" returns reflect the deduction of applicable contingent deferred sales charge (CDSC). Effective December 1, 2004, the period during which a CDSC is applied to withdrawals was shortened to 5 years. The maximum CDSC for Class B shares continues to be 4%. For more complete information, please see the prospectus for details. Note: Shares purchased prior to December 1, 2004 remain subject to the CDSC in effect at the time you purchased those shares. For performance information for shares purchased prior to December 1, 2004, please visit www.pioneerinvestments.com. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Fund | Annual Report | 12/31/08 11 Performance Update | 12/31/08 Class C Shares Investment Returns - -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Pioneer Fund, compared to that of the Standard & Poor's 500 Index. Average Annual Total Returns (As of December 31, 2008) - ---------------------------------------------------------------- If If Period Held Redeemed - ---------------------------------------------------------------- 10 Years -1.10% -1.10% 5 Years -1.80 -1.80 1 Year -34.91 -34.91 - ---------------------------------------------------------------- Expense Ratio (Per prospectus dated May 1, 2008) - ---------------------------------------------------------------- Gross Net - ---------------------------------------------------------------- 1.88% 1.88% - ---------------------------------------------------------------- [THE FOLLOWING DATA IS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL.] Value of $10,000 Investment Pioneer Standard & Poor's Fund 500 Index 12-98 $10,000 $10,000 $11,460 $12,103 12-00 $11,378 $11,002 $10,031 $ 9,695 12-02 $ 7,937 $ 7,553 $ 9,808 $ 9,719 12-04 $10,862 $10,775 $11,465 $11,304 12-06 $13,244 $13,088 $13,758 $13,807 12-08 $ 8,956 $ 8,699 Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. Class C shares held for less than one year are also subject to a 1% contingent deferred sales charge (CDSC). The performance of Class C shares does not reflect the 1% front-end sales charge in effect prior to February 1, 2004. If you paid a 1% sales charge, your returns would be lower than those shown above. "If Held" results represent the percent change in net asset value per share. Returns would have been lower had sales charges been reflected. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 12 Pioneer Fund | Annual Report | 12/31/08 Performance Update | 12/31/08 Class R Shares Investment Returns - -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Pioneer Fund, compared to that of the Standard & Poor's 500 Index. Average Annual Total Returns (As of December 31, 2008) - --------------------------------------------------------------- If If Period Held Redeemed - --------------------------------------------------------------- 10 Years -0.58% -0.58% 5 Years -1.14 -1.14 1 Year -34.46 -34.46 - --------------------------------------------------------------- Expense Ratio (Per prospectus dated May 1, 2008) - --------------------------------------------------------------- Gross Net - --------------------------------------------------------------- 1.42% 1.42% - --------------------------------------------------------------- [THE FOLLOWING DATA IS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL.] Value of $10,000 Investment Pioneer Standard & Poor's Fund 500 Index 12-98 $10,000 $10,000 $11,497 $12,103 12-00 $11,453 $11,002 $10,127 $ 9,695 12-02 $ 8,035 $ 7,553 $ 9,994 $ 9,719 12-04 $11,151 $10,775 $11,851 $11,304 12-06 $13,774 $13,088 $14,401 $13,807 12-08 $ 9,438 $ 8,699 Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. The performance data quoted represents past performance, which is no guarantee of future results. Investment return and principal value will fluctuate, and shares, when redeemed, may be worth more or less than their original cost. The performance of Class R shares for the period prior to the commencement of operations of Class R shares on April 1, 2003 is based on the performance of Class A shares, reduced to reflect the higher distribution and service fees of Class R shares. For the period after April 1, 2003, 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. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Fund | Annual Report | 12/31/08 13 Performance Update | 12/31/08 Class Y Shares Investment Returns - -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Pioneer Fund, compared to that of the Standard & Poor's 500 Index. Average Annual Total Returns (As of December 31, 2008) - --------------------------------------------------------------- If If Period Held Redeemed - --------------------------------------------------------------- 10 Years 0.10% 0.10% 5 Years -0.60 -0.60 1 Year -34.07 -34.07 - --------------------------------------------------------------- Expense Ratio (Per prospectus dated May 1, 2008) - --------------------------------------------------------------- Gross Net - --------------------------------------------------------------- 0.70% 0.70% - --------------------------------------------------------------- [THE FOLLOWING DATA IS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL.] Value of $10,000 Investment Pioneer Standard & Poor's Fund 500 Index 12-98 $10,000 $10,000 $11,583 $12,103 12-00 $11,641 $11,002 $10,390 $ 9,695 12-02 $ 8,320 $ 7,553 $10,411 $ 9,719 12-04 $11,676 $10,775 $12,474 $11,304 12-06 $14,578 $13,088 $15,323 $13,807 12-08 $10,102 $ 8,699 Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. 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. Performance for periods prior to the inception of Class Y shares reflects the NAV performance of the Fund's Class A shares. The performance does not reflect differences in expenses, including the Rule 12b-1 fees applicable to Class A shares. Since fees for Class A shares are generally higher than those of Class Y shares, the performance shown for Class Y shares prior to their inception on May 6, 1999 would have been higher. Class Y shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. 14 Pioneer Fund | Annual Report | 12/31/08 Performance Update | 12/31/08 Class Z Shares Investment Returns - -------------------------------------------------------------------------------- The mountain chart on the right shows the change in value of a $10,000 investment made in Pioneer Fund, compared to that of the Standard & Poor's 500 Index. Average Annual Total Returns (As of December 31, 2008) - ----------------------------------------------------------------- Net Asset Public Offering Period Value (NAV) Price (POP) - ----------------------------------------------------------------- 10 Years -0.21% -0.21% 5 Years -0.84 -0.84 1 Year -34.06 -34.06 - ----------------------------------------------------------------- Expense Ratio (Per prospectus dated May 1, 2008) - ----------------------------------------------------------------- Gross Net - ----------------------------------------------------------------- 0.85% 0.85% - ----------------------------------------------------------------- [THE FOLLOWING DATA IS REPRESENTED AS A MOUNTAIN CHART IN THE PRINTED MATERIAL.] Value of $10,000 Investment Pioneer Standard & Poor's Fund 500 Index 12-98 $10,000 $10,000 $11,554 $12,103 12-00 $11,568 $11,002 $10,280 $ 9,695 12-02 $ 8,198 $ 7,553 $10,212 $ 9,719 12-04 $11,400 $10,775 $12,129 $11,304 12-06 $14,117 $13,088 $14,851 $13,807 12-08 $ 9,792 $ 8,699 Call 1-800-225-6292 or visit www.pioneerinvestments.com for the most recent month-end performance results. Current performance may be lower or higher than the performance data quoted. 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. Performance for periods prior to the inception of Class Z shares reflects the NAV performance of the Fund's Class A shares. The performance does not reflect differences in expenses, including the Rule 12b-1 fees applicable to Class A shares. Since fees for Class A shares are generally higher than those of Class Z shares, the performance shown for Class Z shares prior to their inception on April 30, 2007 would have been higher. Class Z shares are not subject to sales charges and are available for limited groups of eligible investors, including institutional investors. All results are historical and assume the reinvestment of dividends and capital gains. Other share classes are available for which performance and expenses will differ. Performance results reflect any applicable expense waivers in effect during the periods shown. Without such waivers Fund performance would be lower. Waivers may not be in effect for all funds. Certain fee waivers are contractual through a specified period. Otherwise, fee waivers can be rescinded at any time. See the prospectus and financial statements for more information. The net expense ratio reflects contractual expense limitation currently in effect through 5/1/12 for Class Z shares. There can be no assurance that Pioneer will extend the expense limitation beyond such time. Please see the prospectus and financial statements for more information. The performance table and graph do not reflect the deduction of fees and taxes that a shareowner would pay on Fund distributions or the redemption of Fund shares. Pioneer Fund | Annual Report | 12/31/08 15 Comparing Ongoing Fund Expenses As a shareowner in the Fund, you incur two types of costs: (1) ongoing costs, including management fees, distribution and/or service (12b-1) fees, and other Fund expenses; and (2) transaction costs, including sales charges (loads) on purchase payments. This example is intended to help you understand your ongoing expenses (in dollars) of investing in the Fund and to compare these costs with the ongoing costs of investing in other mutual funds. The example is based on an investment of $1,000 at the beginning of the Fund's latest six-month period and held throughout the six months. Using the Tables - -------------------------------------------------------------------------------- Actual Expenses The first table below provides information about actual account values and actual expenses. You may use the information in this table, together with the amount you invested, to estimate the expenses that you paid over the period as follows: (1) Divide your account value by $1,000 Example: an $8,600 account value [divided by] $1,000 = 8.6 (2) Multiply the result in (1) above by the corresponding share class's number in the third row under the heading entitled "Expenses Paid During Period" to estimate the expenses you paid on your account during this period. Expenses Paid on a $1,000 Investment in Pioneer Fund Based on actual returns from July 1, 2008 through December 31, 2008. Share Class A B C R Y Z Beginning Account $ 1,000.00 $ 1,000.00 $ 1,000.00 $ 1,000.00 $ 1,000.00 $ 1,000.00 Value on 7/1/08 - ----------------------------------------------------------------------------------------------------------------------- Ending Account $ 726.93 $ 723.54 $ 724.11 $ 726.61 $ 728.91 $ 728.94 Value on 12/31/08 - ----------------------------------------------------------------------------------------------------------------------- Expenses Paid $ 5.12 $ 9.18 $ 8.54 $ 5.73 $ 3.22 $ 3.22 During Period* - ----------------------------------------------------------------------------------------------------------------------- * Expenses are equal to the Fund's annualized expense ratio of 1.18%, 2.12%, 1.97%, 1.32%, 0.74%, and 0.74% for Class A, Class B, Class C, Class R, Class Y and Class Z shares, respectively, multiplied by the average account value over the period, multiplied by 184/366 (to reflect the one-half year period). 16 Pioneer Fund | Annual Report | 12/31/08 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 Fund Based on a hypothetical 5% per year return before expenses, reflecting the period from July 1, 2008 through December 31, 2008. Share Class A B C R Y I Beginning Account $ 1,000.00 $ 1,000.00 $ 1,000.00 $ 1,000.00 $ 1,000.00 $ 1,000.00 Value on 7/1/08 - -------------------------------------------------------------------------------------------------------------------------- Ending Account Value $ 1,019.20 $ 1,014.48 $ 1,015.23 $ 1,018.50 $ 1,021.42 $ 1,021.42 on 12/31/08 - -------------------------------------------------------------------------------------------------------------------------- Expenses Paid $ 5.99 $ 10.74 $ 9.98 $ 6.70 $ 3.76 $ 3.76 During Period* - -------------------------------------------------------------------------------------------------------------------------- * Expenses are equal to the Fund's annualized expense ratio of 1.18%, 2.12%, 1.97%, 1.32%, 0.74%, and 0.74% for Class A, Class B, Class C, Class R, Class Y and Class Z shares, respectively, multiplied by the average account value over the period, multiplied by 184/366 (to reflect the one-half year period). Pioneer Fund | Annual Report | 12/31/08 17 Schedule of Investments | 12/31/08 Shares Value COMMON STOCKS -- 99.4% ENERGY -- 9.7% Integrated Oil & Gas -- 7.3% 2,504,691 Chevron Corp. $ 185,271,993 1,010,329 Exxon Mobil Corp. (b) 80,654,564 1,450,000 Marathon Oil Corp. 39,672,000 650,000 Royal Dutch Shell Plc (A.D.R.) 34,411,000 -------------- $ 340,009,557 - ------------------------------------------------------------------------------------- Oil & Gas Equipment & Services -- 0.6% 600,000 Schlumberger, Ltd. $ 25,398,000 - ------------------------------------------------------------------------------------- Oil & Gas Exploration & Production -- 1.8% 1,125,502 Apache Corp. (b) $ 83,883,664 -------------- Total Energy $ 449,291,221 - ------------------------------------------------------------------------------------- MATERIALS -- 5.4% Aluminum -- 0.8% 3,106,824 Alcoa, Inc. (b) $ 34,982,838 - ------------------------------------------------------------------------------------- Diversified Chemical -- 1.0% 1,276,700 Dow Chemical Co. $ 19,265,403 1,090,474 E.I. du Pont de Nemours and Co. 27,588,992 -------------- $ 46,854,395 - ------------------------------------------------------------------------------------- Diversified Metals & Mining -- 1.3% 740,000 Freeport-McMoRan Copper & Gold, Inc. (Class B) (b) $ 18,085,600 1,600,000 Rio Tinto Plc 34,682,012 980,000 Teck Cominco, Ltd. (Class B) 4,821,600 468,800 Xstrata Plc 4,375,073 -------------- $ 61,964,285 - ------------------------------------------------------------------------------------- Fertilizers & Agricultural Chemicals -- 0.8% 500,000 Monsanto Co. $ 35,175,000 - ------------------------------------------------------------------------------------- Industrial Gases -- 0.9% 507,700 Air Products & Chemicals, Inc. $ 25,522,079 300,000 Praxair, Inc. 17,808,000 -------------- $ 43,330,079 - ------------------------------------------------------------------------------------- Specialty Chemicals -- 0.6% 787,300 Ecolab, Inc. $ 27,673,595 -------------- Total Materials $ 249,980,192 - ------------------------------------------------------------------------------------- CAPITAL GOODS -- 11.2% Aerospace & Defense -- 3.7% 1,254,200 General Dynamics Corp. $ 72,229,378 300,000 Honeywell International, Inc. (b) 9,849,000 1,669,200 United Technologies Corp. (b) 89,469,120 -------------- $ 171,547,498 - ------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 18 Pioneer Fund | Annual Report | 12/31/08 Shares Value Construction & Farm Machinery & Heavy Trucks -- 4.2% 1,064,400 Caterpillar, Inc. (b) $ 47,546,748 1,591,900 Deere & Co. (b) 61,001,608 2,996,250 PACCAR, Inc. (b) 85,692,750 -------------- $ 194,241,106 - ------------------------------------------------------------------------------------- Electrical Component & Equipment -- 1.3% 1,120,600 Emerson Electric Co. $ 41,025,166 654,100 Rockwell International Corp. 21,088,184 -------------- $ 62,113,350 - ------------------------------------------------------------------------------------- Industrial Conglomerates -- 1.4% 665,200 3M Co. (b) $ 38,275,608 1,532,300 General Electric Co. (b) 24,823,260 -------------- $ 63,098,868 - ------------------------------------------------------------------------------------- Industrial Machinery -- 0.6% 350,000 Illinois Tool Works, Inc. (b) $ 12,267,500 379,950 Parker Hannifin Corp. (b) 16,163,073 -------------- $ 28,430,573 -------------- Total Capital Goods $ 519,431,395 - ------------------------------------------------------------------------------------- TRANSPORTATION -- 5.3% Railroads -- 5.3% 766,500 Burlington Northern, Inc. $ 58,031,715 1,300,000 Canadian National Railway Co. (b) 47,788,000 2,993,600 Norfolk Southern Corp. 140,848,880 -------------- $ 246,668,595 -------------- Total Transportation $ 246,668,595 - ------------------------------------------------------------------------------------- AUTOMOBILES & COMPONENTS -- 1.8% Auto Parts & Equipment -- 1.8% 700,000 BorgWarner, Inc. $ 15,239,000 3,858,000 Johnson Controls, Inc. 70,061,280 -------------- $ 85,300,280 -------------- Total Automobiles & Components $ 85,300,280 - ------------------------------------------------------------------------------------- CONSUMER DURABLES & APPAREL -- 0.6% Apparel, Accessories & Luxury Goods -- 0.6% 1,400,000 Coach, Inc.* $ 29,078,000 -------------- Total Consumer Durables & Apparel $ 29,078,000 - ------------------------------------------------------------------------------------- MEDIA -- 4.8% Movies & Entertainment -- 0.5% 1,079,200 The Walt Disney Co. (b) $ 24,487,048 - ------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 19 Schedule of Investments | 12/31/08 (continued) Shares Value Publishing -- 4.3% 3,494,400 John Wiley & Sons, Inc.+(b) $ 124,330,752 3,121,800 McGraw-Hill Co., Inc. (b) 72,394,542 -------------- $ 196,725,294 -------------- Total Media $ 221,212,342 - ------------------------------------------------------------------------------------- RETAILING -- 3.9% Department Stores -- 0.7% 356,200 J.C. Penney Co., Inc. $ 7,017,140 1,880,100 Nordstrom, Inc. (b) 25,024,131 -------------- $ 32,041,271 - ------------------------------------------------------------------------------------- General Merchandise Stores -- 1.7% 2,284,700 Target Corp. (b) $ 78,890,691 - ------------------------------------------------------------------------------------- Home Improvement Retail -- 1.1% 2,315,200 Lowe's Companies, Inc. (b) $ 49,823,104 - ------------------------------------------------------------------------------------- Specialty Stores -- 0.4% 1,100,000 Staples, Inc. $ 19,712,000 -------------- Total Retailing $ 180,467,066 - ------------------------------------------------------------------------------------- FOOD & DRUG RETAILING -- 3.1% Drug Retail -- 2.3% 1,213,800 CVS/Caremark Corp. $ 34,884,612 2,854,500 Walgreen Co. 70,420,515 -------------- $ 105,305,127 - ------------------------------------------------------------------------------------- Food Distributors -- 0.8% 1,732,400 Sysco Corp. $ 39,741,256 -------------- Total Food & Drug Retailing $ 145,046,383 - ------------------------------------------------------------------------------------- FOOD, BEVERAGE & TOBACCO -- 10.5% Packaged Foods & Meats -- 7.6% 1,716,000 Campbell Soup Co. (b) $ 51,497,160 910,600 General Mills, Inc. 55,318,950 1,506,750 H.J. Heinz Co., Inc. (b) 56,653,800 1,925,000 Hershey Foods Corp. (b) 66,874,500 676,500 Kellogg Co. 29,664,525 2,500,000 Kraft Foods, Inc. 67,125,000 600,000 Nestle SA 23,277,068 -------------- $ 350,411,003 - ------------------------------------------------------------------------------------- Soft Drinks -- 2.9% 1,000,000 Coca-Cola Co. (b) $ 45,270,000 1,648,890 PepsiCo, Inc. 90,309,705 -------------- $ 135,579,705 -------------- Total Food, Beverage & Tobacco $ 485,990,708 - ------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 20 Pioneer Fund | Annual Report | 12/31/08 Shares Value HOUSEHOLD & PERSONAL PRODUCTS -- 2.9% Household Products -- 2.5% 303,300 Clorox Co. $ 16,851,348 1,434,200 Colgate-Palmolive Co. (b) 98,300,068 -------------- $ 115,151,416 - ------------------------------------------------------------------------------------- Personal Products -- 0.4% 581,300 Estee Lauder Co. (b) $ 17,997,048 -------------- Total Household & Personal Products $ 133,148,464 - ------------------------------------------------------------------------------------- HEALTH CARE EQUIPMENT & SERVICES -- 6.5% Health Care Equipment -- 6.5% 1,540,300 Becton, Dickinson & Co. $ 105,341,117 952,600 C. R. Bard, Inc. 80,266,076 1,073,100 Medtronic, Inc. 33,716,802 1,512,100 St. Jude Medical, Inc.* 49,838,816 750,000 Stryker Corp. 29,962,500 -------------- $ 299,125,311 -------------- Total Health Care Equipment & Services $ 299,125,311 - ------------------------------------------------------------------------------------- PHARMACEUTICALS & BIOTECHNOLOGY -- 8.1% Pharmaceuticals -- 8.1% 1,599,700 Abbott Laboratories, Inc. $ 85,375,989 837,837 Eli Lilly & Co. (b) 33,739,696 975,403 Merck & Co., Inc. 29,652,251 2,800,000 Pfizer, Inc. 49,588,000 389,800 Roche Holdings AG 59,071,622 3,542,800 Schering-Plough Corp. 60,333,884 1,379,081 Teva Pharmaceutical Industries, Ltd. (A.D.R.) (b) 58,707,478 -------------- $ 376,468,920 -------------- Total Pharmaceuticals & Biotechnology $ 376,468,920 - ------------------------------------------------------------------------------------- BANKS -- 3.6% Diversified Banks -- 2.9% 2,480,307 U.S. Bancorp (b) $ 62,032,478 2,455,400 Wells Fargo & Co. (b) 72,385,192 -------------- $ 134,417,670 - ------------------------------------------------------------------------------------- Regional Banks -- 0.7% 362,689 SunTrust Banks, Inc. (b) $ 10,713,833 939,500 Zions Bancorporation (b) 23,027,145 -------------- $ 33,740,978 -------------- Total Banks $ 168,158,648 - ------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 21 Schedule of Investments | 12/31/08 (continued) Shares Value DIVERSIFIED FINANCIALS -- 3.2% Asset Management & Custody Banks -- 2.3% 520,000 Franklin Resources, Inc. $ 33,165,600 1,514,693 T. Rowe Price Associates, Inc. (b) 53,680,720 666,500 The Bank of New York Mellon Corp. 18,881,945 -------------- $ 105,728,265 - ------------------------------------------------------------------------------------- Consumer Finance -- 0.2% 626,500 American Express Co. (b) $ 11,621,575 - ------------------------------------------------------------------------------------- Diversified Financial Services -- 0.7% 1,206,300 Bank of America Corp. $ 16,984,704 500,000 J.P. Morgan Chase & Co. 15,765,000 -------------- $ 32,749,704 -------------- Total Diversified Financials $ 150,099,544 - ------------------------------------------------------------------------------------- INSURANCE -- 2.8% Life & Health Insurance -- 0.2% 229,500 Aflac, Inc. $ 10,520,280 - ------------------------------------------------------------------------------------- Property & Casualty Insurance -- 2.6% 2,348,400 Chubb Corp. $ 119,768,400 -------------- Total Insurance $ 130,288,680 - ------------------------------------------------------------------------------------- SOFTWARE & SERVICES -- 2.4% Application Software -- 0.6% 1,240,400 Adobe Systems, Inc.* $ 26,408,116 - ------------------------------------------------------------------------------------- Data Processing & Outsourced Services -- 1.8% 1,159,200 Automatic Data Processing, Inc. $ 45,602,928 552,800 DST Systems, Inc.* (b) 20,995,344 551,250 Fiserv, Inc.* 20,048,963 -------------- $ 86,647,235 -------------- Total Software & Services $ 113,055,351 - ------------------------------------------------------------------------------------- TECHNOLOGY HARDWARE & EQUIPMENT -- 6.3% Communications Equipment -- 2.0% 1,850,000 Cisco Systems, Inc.* $ 30,155,000 3,978,600 Nokia Corp. (A.D.R.) 62,066,160 -------------- $ 92,221,160 - ------------------------------------------------------------------------------------- Computer Hardware -- 2.7% 2,726,211 Hewlett-Packard Co. $ 98,934,197 300,000 IBM Corp. (b) 25,248,000 -------------- $ 124,182,197 - ------------------------------------------------------------------------------------- Computer Storage & Peripherals -- 0.3% 1,520,500 EMC Corp.* (b) $ 15,919,635 - ------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 22 Pioneer Fund | Annual Report | 12/31/08 Shares Value Office Electronics -- 1.3% 1,865,850 Canon, Inc. (A.D.R.) (b) $ 58,587,690 -------------- Total Technology Hardware & Equipment $ 290,910,682 - --------------------------------------------------------------------------------------------- SEMICONDUCTORS -- 2.6% Semiconductor Equipment -- 0.6% 2,496,500 Applied Materials, Inc. $ 25,289,545 - --------------------------------------------------------------------------------------------- Semiconductors -- 2.0% 3,511,300 Intel Corp. (b) $ 51,475,658 2,753,500 Texas Instruments, Inc. (b) 42,734,320 -------------- $ 94,209,978 -------------- Total Semiconductors $ 119,499,523 - --------------------------------------------------------------------------------------------- TELECOMMUNICATION SERVICES -- 2.6% Integrated Telecommunication Services -- 2.6% 2,663,867 AT&T Corp. $ 75,920,210 1,026,306 Verizon Communications, Inc. 34,791,773 1,029,109 Windstream Corp. 9,467,803 -------------- $ 120,179,786 -------------- Total Telecommunication Services $ 120,179,786 - --------------------------------------------------------------------------------------------- UTILITIES -- 2.1% Electric Utilities -- 1.6% 300,000 FirstEnergy Corp. $ 14,574,000 600,000 PPL Corp. 18,414,000 1,112,400 Southern Co. 41,158,800 -------------- $ 74,146,800 - --------------------------------------------------------------------------------------------- Multi-Utilities -- 0.5% 745,100 Public Service Enterprise Group, Inc. $ 21,734,567 -------------- Total Utilities $ 95,881,367 - --------------------------------------------------------------------------------------------- TOTAL COMMON STOCKS (Cost $3,739,575,373) $4,609,282,458 - --------------------------------------------------------------------------------------------- Principal Amount TEMPORARY CASH INVESTMENTS -- 10.9% Repurchase Agreement -- 0.5% $23,000,000 Barclays Plc, 0.03%, dated 12/31/08, repurchase price of $23,000,000 plus accrued interest on 1/2/09 collateralized by the following: $8,253,897 Federal National Mortgage Association, 4.0 - 5.0%, 9/1/23 - 12/1/33 $2,247,111 Federal Home Loan Mortgage Corp., 5.924%, 1/1/37 $18,696,063 Federal National Mortgage Association (ARM), 4.684 - 5.551%, 9/1/35 - 4/1/38 $ 23,000,000 - --------------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 23 Schedule of Investments | 12/31/08 (continued) Principal Amount Value Securities Lending Collateral -- 10.4% (c) Certificates of Deposit: $11,175,870 Abbey National Plc, 3.15%, 8/13/09 $ 11,175,870 11,174,351 Bank of Nova Scotia, 3.21%, 5/5/09 11,174,351 17,859,885 Bank of Scotland NY, 2.92%, 6/5/09 17,859,885 20,116,565 Barclays Bank, 1.5%, 5/27/09 20,116,565 3,553,226 Calyon NY, 4.62%, 1/16/09 3,553,226 22,351,739 CBA, 4.87%, 7/16/09 22,351,739 20,116,565 DNB NOR Bank ASA NY, 3.04%, 6/5/09 20,116,565 20,474,193 Intesa SanPaolo S.p.A., 1.44%, 5/22/09 20,474,193 1,294,641 NORDEA NY, 4.13%, 4/9/09 1,294,641 16,763,804 Royal Bank of Canada NY, 2.7%, 8/7/09 16,763,804 11,175,870 Royal Bank of Scotland, 3.06%, 3/5/09 11,175,870 2,234,139 Skandinavian Enskilda Bank NY, 3.06%, 2/13/09 2,234,139 22,351,739 Societe Generale, 3.29%, 9/4/09 22,351,739 20,116,565 Svenska Bank NY, 4.61%, 7/8/09 20,116,565 22,351,739 U.S. Bank NA, 2.25%, 8/24/09 22,351,739 -------------- $ 223,110,891 - ------------------------------------------------------------------------------------- Commercial Paper: 21,949,408 American Honda Finance Corp., 4.95%, 7/14/09 $ 21,949,408 2,129,874 BBVA U.S., 2.83%, 3/12/09 2,129,874 11,175,870 CME Group, Inc., 2.9%, 8/6/09 11,175,870 11,174,687 General Electric Capital Corp., 2.86%, 3/16/09 11,174,687 22,351,739 HSBC Bank, Inc., 2.5%, 8/14/09 22,351,739 11,175,870 IBM, 2.39%, 9/25/09 11,175,870 20,116,565 Met Life Global Funding, 3.19%, 6/12/09 20,116,565 22,351,739 Monumental Global Funding, Ltd., 2.5%, 8/17/09 22,351,739 20,116,565 New York Life Global, 2.13%, 09/04/09 20,116,565 18,998,978 Westpac Banking Corp., 2.34%, 6/1/09 18,998,977 -------------- $ 161,541,294 - ------------------------------------------------------------------------------------- Tri-party Repurchase Agreements: 3,797,113 Barclays Capital Markets, 0.5%, 1/2/09 $ 3,797,113 - ------------------------------------------------------------------------------------- 49,173,826 Deutsche Bank, 0.25%, 1/2/09 49,173,826 -------------- $ 52,970,939 - ------------------------------------------------------------------------------------- Time Deposit: 22,351,739 BNP Paribas, 0.01%, 1/2/09 $ 22,351,739 - ------------------------------------------------------------------------------------- Shares Money Market Mutual Fund: 5,587,935 Columbia Government Reserves Fund, 0.82%, 1/2/09 $ 5,587,935 16,763,804 JP Morgan, U.S. Government Money Market Fund, 0.98%, 1/2/09 16,763,804 -------------- $ 22,351,739 -------------- Total Security Lending Collateral $ 482,326,602 - ------------------------------------------------------------------------------------- The accompanying notes are an integral part of these financial statements. 24 Pioneer Fund | Annual Report | 12/31/08 Value TOTAL TEMPORARY CASH INVESTMENTS (Cost $505,326,602) $ 505,326,602 - ------------------------------------------------------------------------------------- TOTAL INVESTMENT IN SECURITIES -- 110.3% (Cost $4,244,901,975) (a) $5,114,609,060 - ------------------------------------------------------------------------------------- OTHER ASSETS AND LIABILITIES -- (10.3)% $ (479,321,323) - ------------------------------------------------------------------------------------- TOTAL NET ASSETS -- 100.0% $4,635,287,737 ===================================================================================== * Non-income producing security. + Investment held by the fund representing 5% or more of voting stock of such company. (A.D.R.) American Depositary Receipt (a) At December 31, 2008, the net unrealized gain on investments based on cost for federal income tax purposes of $4,253,112,045 was as follows: Aggregate gross unrealized gain for all investments in which there is an excess of value over tax cost $1,531,297,757 Aggregate gross unrealized loss for all investments in which there is an excess of tax cost over value (669,800,742) -------------- Net unrealized gain $ 861,497,015 ============== (b) At December 31, 2008, the following securities were out on loan: Shares Security Value 32,700 3M Co. $1,881,558 3,017,200 Alcoa, Inc. 33,973,672 24,400 American Express Co. 452,620 31,100 Apache Corp. 2,317,883 12,000 Campbell Soup Co. 360,120 47,000 Canadian National Railway Co. 1,727,720 225,300 Canon, Inc. (A.D.R.) 7,074,420 173,600 Caterpillar, Inc. 7,754,712 183,000 Coca-Cola Co. 8,284,410 36,900 Colgate-Palmolive Co. 2,529,126 10,300 Deere & Co. 394,696 336,000 DST Systems, Inc.* 12,761,280 20,000 Eli Lilly & Co. 805,400 118,600 EMC Corp.* 1,241,742 291,700 Estee Lauder Co. 9,031,032 10,000 Exxon Mobil Corp. 798,300 692,200 Freeport-McMoRan Copper & Gold, Inc. (Class B) 16,917,368 200,000 General Electric Co. 3,240,000 514,000 H.J. Heinz Co., Inc. 19,326,400 900,400 Hershey Foods Corp. 31,279,896 The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 25 Schedule of Investments | 12/31/08 (continued) Shares Security Value 30,500 Honeywell International, Inc. 1,001,315 100 Illinois Tool Works, Inc. 3,505 26,800 Intel Corp. 392,888 5,000 IBM Corp.* 420,800 5,500 John Wiley & Sons, Inc. 195,690 200 Lowe's Companies, Inc. 4,304 1,300,000 McGraw-Hill Co., Inc. 30,147,000 1,668,200 Nordstrom, Inc. 22,203,742 1,366,500 PACCAR, Inc. 39,081,900 94,000 Parker Hannifin Corp. 3,998,760 358,600 SunTrust Banks, Inc. 10,593,044 1,473,300 T. Rowe Price Associates, Inc. 52,213,752 2,247,300 Target Corp. 77,599,269 702,439 Teva Pharmaceutical Industries, Ltd. 29,902,828 248,500 Texas Instruments, Inc. 3,856,720 115,800 United Technologies Corp. 6,206,880 12,300 U.S. Bancorp 308,730 639,100 The Walt Disney Co. 14,501,179 187,800 Wells Fargo & Co. 5,536,344 763,600 Zions Bancorporation 18,715,836 - --------------------------------------------------------------------- Total $479,036,841 ===================================================================== (c) Securities lending collateral is managed by Credit Suisse New York Branch. Purchases and sales of securities (excluding temporary cash investments) for the year ended December 31, 2008 aggregated $708,954,773 and $1,007,599,793, respectively. Various inputs are used in determining the value of the Fund's investments. These inputs are summarized in the three broad levels listed below. Highest priority is given to Level 1 inputs and lowest priority is given to Level 3. Level 1 -- quoted prices in active markets for identical securities Level 2 -- other significant observable inputs (including quoted prices for similar securities, interest rates, prepayment speeds, credit risk, etc.) Level 3 -- significant unobservable inputs (including the Fund's own assumptions in determining fair value of investments) The following is a summary of the inputs used as of December 31, 2008, in valuing the Fund's assets: Investments Valuation Inputs in Securities Level 1 -- Quoted Prices $4,609,282,458 Level 2 -- Other Significant Observable Inputs 505,326,602 Level 3 -- Significant Unobservable Inputs - ------------------------------------------------------------------ Total $5,114,609,060 ================================================================== The accompanying notes are an integral part of these financial statements. 26 Pioneer Fund | Annual Report | 12/31/08 Statement of Assets and Liabilities | 12/31/08 ASSETS: Investment in securities of unaffiliated issuers, at value (including securities loaned of $479,036,841) (cost $4,237,154,375) $4,990,278,308 Investment in securities of affiliated issuers, at value (cost $7,747,600) 124,330,752 - ---------------------------------------------------------------------------------------- Total investment in securities, at value (cost $4,244,901,975) $5,114,609,060 Cash 19,049,948 Receivables -- Fund shares sold 3,922,385 Dividends, interest and foreign taxes withheld 11,537,527 Other 79,478 - ---------------------------------------------------------------------------------------- Total assets $5,149,198,398 - ---------------------------------------------------------------------------------------- LIABILITIES: Payables -- Investment securities purchased $ 24,234,012 Fund shares repurchased 5,321,992 Upon return of securities loaned 482,326,602 Due to affiliates 1,322,036 Accrued expenses 706,019 - ---------------------------------------------------------------------------------------- Total liabilities $ 513,910,661 - ---------------------------------------------------------------------------------------- NET ASSETS: Paid-in capital $3,940,080,621 Accumulated net realized loss on investments and foreign currency transactions (174,478,584) Net unrealized gain on investments 869,707,085 Net unrealized loss on forward foreign currency contracts and other assets and liabilities denominated in foreign currencies (21,385) - ---------------------------------------------------------------------------------------- Total net assets $4,635,287,737 - ---------------------------------------------------------------------------------------- NET ASSET VALUE PER SHARE: (No par value, unlimited number of shares authorized) Class A (based on $3,767,132,025/129,308,750 shares) $ 29.13 Class B (based on $134,093,837/4,717,025 shares) $ 28.43 Class C (based on $169,361,908/6,057,302 shares) $ 27.96 Class R (based on $102,070,450/3,499,487 shares) $ 29.17 Class Y (based on $462,571,826/15,832,778 shares) $ 29.22 Class Z (based on $57,691/1,976 shares) $ 29.20 MAXIMUM OFFERING PRICE: Class A ($29.13 [divided by] 94.25%) $ 30.91 ======================================================================================== The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 27 Statement of Operations For the Year Ended 12/31/08 INVESTMENT INCOME: Dividends (net of foreign taxes withheld of $1,349,135 and including income from affiliated issuers of $1,747,200) $ 141,821,073 Interest 24,982 Income from securities loaned, net 2,725,128 Other income 443,291 - ------------------------------------------------------------------------------------------------------ Total investment income $ 145,014,474 - ------------------------------------------------------------------------------------------------------ EXPENSES: Management fees Basic Fee $ 37,743,175 Performance Adjustment 3,013,393 Transfer agent fees Class A 9,399,297 Class B 730,589 Class C 277,290 Class R 6,654 Class Y 12,274 Class Z 6 Distribution fees Class A 12,803,463 Class B 2,164,043 Class C 2,393,373 Class R 700,711 Administrative fees 1,887,278 Shareholder communications expense 3,210,171 Custodian fees 267,493 Registration fees 183,799 Professional fees 458,482 Printing expense 182,390 Fees and expenses of nonaffiliated trustees 203,273 Miscellaneous 1,161,557 - ------------------------------------------------------------------------------------------------------ Total expenses $ 76,798,711 Less fees paid indirectly (270,760) - ------------------------------------------------------------------------------------------------------ Net expenses $ 76,527,951 - ------------------------------------------------------------------------------------------------------ Net investment income $ 68,486,523 - ------------------------------------------------------------------------------------------------------ REALIZED AND UNREALIZED LOSS ON INVESTMENTS AND FOREIGN CURRENCY TRANSACTIONS: Net realized loss on: Investments $ (164,838,503) Forward foreign currency contracts and other assets and liabilities denominated in foreign currencies (482,819) $ (165,321,322) - ------------------------------------------------------------------------------------------------------ Change in net unrealized gain on: Investments $(2,398,372,528) Forward foreign currency contracts and other assets and liabilities denominated in foreign currencies (23,736) $(2,398,396,264) - ------------------------------------------------------------------------------------------------------ Net loss on investments and foreign currency transactions $(2,563,717,586) - ------------------------------------------------------------------------------------------------------ Net decrease in net assets resulting from operations $(2,495,231,063) - ------------------------------------------------------------------------------------------------------ The accompanying notes are an integral part of these financial statements. 28 Pioneer Fund | Annual Report | 12/31/08 Statement of Changes in Net Assets For the Years Ended 12/31/08 and 12/30/07, respectively Year Ended Year Ended 12/31/08 12/31/07 FROM OPERATIONS: Net investment income $ 68,486,523 $ 61,216,461 Net realized gain (loss) on investments and foreign currency transactions (165,321,322) 603,260,511 Change in net unrealized gain (loss) on investments and foreign currency transactions (2,398,396,264) (288,055,194) - ------------------------------------------------------------------------------------------------------ Net increase (decrease) in net assets resulting from operations $ (2,495,231,063) $ 376,421,778 - ------------------------------------------------------------------------------------------------------ DISTRIBUTIONS TO SHAREOWNERS: Net investment income: Class A ($0.45 and $0.41 per share, respectively) $ (58,113,191) $ (54,679,851) Class C ($0.16 and $0.06 per share, respectively) (954,727) (374,134) Class R ($0.39 and $0.35 per share, respectively) (1,370,041) (1,050,005) Class Y ($0.63 and $0.61 per share, respectively) (8,052,122) (5,680,764) Class Z ($0.62 and $0.47 per share, respectively) (1,223) (932) Net realized gain: Class A ($0.86 and $3.57 per share, respectively) (107,813,529) (454,506,280) Class B ($0.86 and $3.57 per share, respectively) (4,038,863) (22,503,839) Class C ($0.86 and $3.57 per share, respectively) (4,983,947) (22,180,345) Class R ($0.86 and $3.57 per share, respectively) (2,865,572) (11,330,183) Class Y ($0.86 and $3.57 per share, respectively) (12,575,258) (34,284,341) Class Z ($0.86 and $3.57 per share, respectively) (1,689) (7,057) - ------------------------------------------------------------------------------------------------------ Total distributions to shareowners $ (200,770,162) $ (606,597,731) - ------------------------------------------------------------------------------------------------------ FROM FUND SHARE TRANSACTIONS: Net proceeds from sale of shares $ 745,042,373 $ 846,660,776 Reinvestment of distributions 182,541,127 545,172,182 Cost of shares repurchased (1,137,254,951) (1,523,672,524) - ------------------------------------------------------------------------------------------------------ Net decrease in net assets resulting from Fund share transactions $ (209,671,451) $ (131,839,566) - ------------------------------------------------------------------------------------------------------ Net decrease in net assets $ (2,905,672,676) $ (362,015,519) NET ASSETS: Beginning of year 7,540,960,413 7,902,975,932 - ------------------------------------------------------------------------------------------------------ End of year $ 4,635,287,737 $ 7,540,960,413 - ------------------------------------------------------------------------------------------------------ Undistributed net investment income $ 0 $ 0 - ------------------------------------------------------------------------------------------------------ The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 29 Statement of Changes in Net Assets (continued) '08 Shares '08 Amount '07 Shares '07 Amount Class A Shares sold 8,974,415 $ 351,431,314 10,311,922 $ 515,097,783 Reinvestment of distributions 5,036,737 152,899,602 10,133,411 465,855,072 Less shares repurchased (20,696,437) (812,904,400) (23,353,347) (1,177,249,539) - ----------------------------------------------------------------------------------------------------- Net decrease (6,685,285) $ (308,573,484) (2,908,014) $ (196,296,684) ===================================================================================================== Class B Shares sold 417,148 $ 15,509,729 527,816 $ 25,527,228 Reinvestment of distributions 130,353 3,530,937 429,811 19,045,228 Less shares repurchased (2,402,976) (93,105,049) (3,018,531) (147,248,151) - ----------------------------------------------------------------------------------------------------- Net decrease (1,855,475) $ (74,064,383) (2,060,904) $ (102,675,695) ===================================================================================================== Class C Shares sold 1,026,861 $ 36,243,313 1,087,496 $ 51,404,697 Reinvestment of distributions 129,430 3,544,945 315,373 13,826,369 Less shares repurchased (1,745,954) (65,366,415) (1,428,783) (68,898,510) - ----------------------------------------------------------------------------------------------------- Net decrease (589,663) $ (25,578,157) (25,914) $ (3,667,444) ===================================================================================================== Class R Shares sold 698,097 $ 26,750,613 1,587,110 $ 79,939,482 Reinvestment of distributions 138,657 4,180,459 265,657 12,201,241 Less shares repurchased (816,099) (30,650,247) (542,531) (27,436,367) - ----------------------------------------------------------------------------------------------------- Net increase 20,655 $ 280,825 1,310,236 $ 64,704,356 ===================================================================================================== Class Y Shares sold 8,127,028 $ 315,107,404 3,472,708 $ 174,591,582 Reinvestment of distributions 601,531 18,385,184 740,778 34,244,272 Less shares repurchased (3,388,116) (135,228,840) (2,043,668) (102,839,957) - ----------------------------------------------------------------------------------------------------- Net increase 5,340,443 $ 198,263,748 2,169,818 $ 105,995,897 ===================================================================================================== Class Z* Shares sold -- $ -- 1,976 $ 100,004 - ----------------------------------------------------------------------------------------------------- Net increase -- $ -- 1,976 $ 100,004 ===================================================================================================== * Class Z shares were first publicly offered on April 30, 2007. The accompanying notes are an integral part of these financial statements. 30 Pioneer Fund | Annual Report | 12/31/08 Financial Highlights Year Ended Year Ended 12/31/08 12/31/07 Class A Net asset value, beginning of period $ 46.32 $ 48.10 - ------------------------------------------------------------------------------------- Increase from investment operations: Net investment income $ 0.45 $ 0.41 Net realized and unrealized gain (loss) on investments (16.33) 1.79 - ------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ (15.88) $ 2.20 Distributions to shareowners: Net investment income (0.45) (0.41) Net realized gain (0.86) (3.57) - ------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (17.19) $ (1.78) - ------------------------------------------------------------------------------------- Net asset value, end of period $ 29.13 $ 46.32 ===================================================================================== Total return* (34.38)% 4.71% Ratio of net expenses to average net assets+ 1.19% 1.09% Ratio of net investment income to average net assets+ 1.11% 0.81% Portfolio turnover rate 11% 10% Net assets, end of period (in thousands) $3,767,132 $6,299,615 Ratios with reductions for fees paid indirectly: Net expenses 1.18% 1.08% Net investment income 1.12% 0.82% ===================================================================================== Year Ended Year Ended Year Ended 12/31/06 12/31/05 12/31/04 Class A Net asset value, beginning of period $ 44.21 $ 42.06 $ 38.00 - ---------------------------------------------------------------------------------------------------- Increase from investment operations: Net investment income $ 0.43 $ 0.37 $ 0.35 Net realized and unrealized gain (loss) on investments 6.72 2.31 4.05 - ---------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 7.15 $ 2.68 $ 4.40 Distributions to shareowners: Net investment income (0.43) (0.39) (0.34) Net realized gain (2.83) (0.14) -- - ---------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ 3.89 $ 2.15 $ 4.06 - ---------------------------------------------------------------------------------------------------- Net asset value, end of period $ 48.10 $ 44.21 $ 42.06 ==================================================================================================== Total return* 16.39% 6.40% 11.64% Ratio of net expenses to average net assets+ 1.11% 1.08% 1.06% Ratio of net investment income to average net assets+ 0.90% 0.88% 0.90% Portfolio turnover rate 9% 13% 14% Net assets, end of period (in thousands) $6,681,712 $5,648,986 $5,626,270 Ratios with reductions for fees paid indirectly: Net expenses 1.10% 1.08% 1.06% Net investment income 0.91% 0.88% 0.90% ==================================================================================================== * Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period, and no sales charges. Total return would be reduced if sales charges were taken into account. + Ratio with no reduction for fees paid indirectly. The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 31 Financial Highlights (continued) Year Ended Year Ended 12/31/08 12/31/07 Class B Net asset value, beginning of period $ 45.11 $ 46.98 - ---------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income (loss) $ 0.07 $ (0.04) Net realized and unrealized gain (loss) on investments (15.89) 1.74 - ---------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ (15.82) $ 1.70 Distributions to shareowners: Net investment income -- -- Net realized gain (0.86) (3.57) - ---------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ (16.68) $ (1.87) - ---------------------------------------------------------------------------------------- Net asset value, end of period $ 28.43 $ 45.11 ========================================================================================= Total return* (34.99)% 3.76% Ratio of net expenses to average net assets+ 2.13% 1.99% Ratio of net investment income (loss) to average net assets+ 0.14% (0.10)% Portfolio turnover rate 11% 10% Net assets, end of period (in thousands) $134,094 $296,491 Ratios with reduction for fees paid indirectly: Net expenses 2.12% 1.97% Net investment income (loss) 0.15% (0.08)% ========================================================================================= Year Ended Year Ended Year Ended 12/31/06 12/31/05 12/31/04 Class B Net asset value, beginning of period $ 43.21 $ 41.15 $ 37.18 - ------------------------------------------------------------------------------------------------------ Increase (decrease) from investment operations: Net investment income (loss) $ 0.03 $ (0.02) $ 0.01 Net realized and unrealized gain (loss) on investments 6.58 2.24 3.96 - ------------------------------------------------------------------------------------------------------ Net increase (decrease) from investment operations $ 6.61 $ 2.22 $ 3.97 Distributions to shareowners: Net investment income (0.01) (0.02) -- Net realized gain (2.83) (0.14) -- - ------------------------------------------------------------------------------------------------------ Net increase (decrease) in net asset value $ 3.77 $ 2.06 $ 3.97 - ------------------------------------------------------------------------------------------------------ Net asset value, end of period $ 46.98 $ 43.21 $ 41.15 ======================================================================================================= Total return* 15.43% 5.39% 10.68% Ratio of net expenses to average net assets+ 1.97% 2.01% 1.93% Ratio of net investment income (loss) to average net assets+ 0.04% (0.05)% 0.02% Portfolio turnover rate 9% 13% 14% Net assets, end of period (in thousands) $405,566 $474,139 $538,786 Ratios with reduction for fees paid indirectly: Net expenses 1.96% 2.01% 1.93% Net investment income (loss) 0.05% (0.05)% 0.02% ======================================================================================================= * Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period, and no sales charges. Total return would be reduced if sales charges were taken into account. + Ratio with no reduction for fees paid indirectly. The accompanying notes are an integral part of these financial statements. 32 Pioneer Fund | Annual Report | 12/31/08 Year Ended Year Ended 12/31/08 12/31/07 Class C Net asset value, beginning of period $ 44.55 $ 46.44 - ------------------------------------------------------------------------------------ Increase from investment operations: Net investment income $ 0.13 $ 0.02 Net realized and unrealized gain (loss) on investments (15.70) 1.72 - ------------------------------------------------------------------------------------ Net increase (decrease) from investment operations $ (15.57) $ 1.74 Distributions to shareowners: Net investment income (0.16) (0.06) Net realized gain (0.86) (3.57) - ------------------------------------------------------------------------------------ Net increase (decrease) in net asset value $ (16.59) $ (1.89) - ------------------------------------------------------------------------------------ Net asset value, end of period $ 27.96 $ 44.55 ==================================================================================== Total return* (34.91)% 3.88% Ratio of net expenses to average net assets+ 1.97% 1.88% Ratio of net investment income to average net assets+ 0.32% 0.02% Portfolio turnover rate 11% 10% Net assets, end of period (in thousands) $169,362 $296,094 Ratios with reduction for fees paid indirectly: Net expenses 1.97% 1.87% Net investment income 0.32% 0.03% ==================================================================================== Year Ended Year Ended Year Ended 12/31/06 12/31/05 12/31/04 Class C Net asset value, beginning of period $ 42.78 $ 40.73 $ 36.84 - -------------------------------------------------------------------------------------------------- Increase from investment operations: Net investment income $ 0.06 $ 0.04 $ 0.04 Net realized and unrealized gain (loss) on investments 6.52 2.22 3.91 - -------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 6.58 $ 2.26 $ 3.95 Distributions to shareowners: Net investment income (0.09) (0.07) (0.06) Net realized gain (2.83) (0.14) -- - -------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ 3.66 $ 2.05 $ 3.89 - -------------------------------------------------------------------------------------------------- Net asset value, end of period $ 46.44 $ 42.78 $ 40.73 ================================================================================================== Total return* 15.52% 5.55% 10.74% Ratio of net expenses to average net assets+ 1.89% 1.87% 1.84% Ratio of net investment income to average net assets+ 0.12% 0.09% 0.11% Portfolio turnover rate 9% 13% 14% Net assets, end of period (in thousands) $309,868 $292,453 $313,420 Ratios with reduction for fees paid indirectly: Net expenses 1.88% 1.87% 1.84% Net investment income 0.13% 0.09% 0.11% ================================================================================================== * Assumes initial investment at net asset value at the beginning of each period, reinvestment of all distributions, the complete redemption of the investment at net asset value at the end of each period, and no sales charges. Total return would be reduced if sales charges were taken into account. + Ratio with no reduction for fees paid indirectly. The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 33 Financial Highlights (continued) Year Ended Year Ended 12/31/08 12/31/07 Class R Net asset value, beginning of period $ 46.37 $ 48.16 - ------------------------------------------------------------------------------------ Increase from investment operations: Net investment income $ 0.40 $ 0.33 Net realized and unrealized gain (loss) on investments (16.35) 1.80 - ------------------------------------------------------------------------------------ Net increase (decrease) from investment operations $ (15.95) $ 2.13 Distributions to shareowners: Net investment income (0.39) (0.35) Net realized gain (0.86) (3.57) - ------------------------------------------------------------------------------------ Net increase (decrease) in net asset value $ (17.20) $ (1.79) - ------------------------------------------------------------------------------------ Net asset value, end of period $ 29.17 $ 46.37 ==================================================================================== Total return* (34.46)% 4.56% Ratio of net expenses to average net assets+ 1.32% 1.23% Ratio of net investment income to average net assets+ 0.99% 0.68% Portfolio turnover rate 11% 10% Net assets, end of period (in thousands) $102,070 $161,311 Ratios with reduction for fees paid indirectly: Net expenses 1.32% 1.23% Net investment income 0.99% 0.68% ==================================================================================== Year Ended Year Ended Year Ended 12/31/06 12/31/05 12/31/04 Class R Net asset value, beginning of period $ 44.27 $ 42.11 $ 38.06 - --------------------------------------------------------------------------------------------------- Increase from investment operations: Net investment income $ 0.34 $ 0.30 $ 0.29 Net realized and unrealized gain (loss) on investments 6.76 2.33 4.09 - --------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 7.10 $ 2.63 $ 4.38 Distributions to shareowners: Net investment income (0.38) (0.33) (0.33) Net realized gain (2.83) (0.14) -- - --------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ 3.89 $ 2.16 $ 4.05 - --------------------------------------------------------------------------------------------------- Net asset value, end of period $ 48.16 $ 44.27 $ 42.11 =================================================================================================== Total return* 16.23% 6.28% 11.58% Ratio of net expenses to average net assets+ 1.26% 1.21% 1.14% Ratio of net investment income to average net assets+ 0.75% 0.75% 0.89% Portfolio turnover rate 9% 13% 14% Net assets, end of period (in thousands) $104,439 $51,194 $16,525 Ratios with reduction for fees paid indirectly: Net expenses 1.26% 1.21% 1.14% Net investment income 0.75% 0.75% 0.89% =================================================================================================== * 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 each end of each period. + Ratio with no reduction for fees paid indirectly. The accompanying notes are an integral part of these financial statements. 34 Pioneer Fund | Annual Report | 12/31/08 Year Ended Year Ended 12/31/08 12/31/07 Class Y Net asset value, beginning of period $ 46.45 $ 48.23 - ------------------------------------------------------------------------------------ Increase from investment operations: Net investment income $ 0.61 $ 0.60 Net realized and unrealized gain (loss) on investments (16.35) 1.80 - ------------------------------------------------------------------------------------ Net increase (decrease) from investment operations $ (15.74) $ 2.40 Distributions to shareowners: Net investment income (0.63) (0.61) Net realized gain (0.86) (3.57) - ------------------------------------------------------------------------------------ Net increase (decrease) in net asset value $ (17.23) $ (1.78) - ------------------------------------------------------------------------------------ Net asset value, end of period $ 29.22 $ 46.45 ==================================================================================== Total return* (34.07)% 5.11% Ratio of net expenses to average net assets+ 0.74% 0.70% Ratio of net investment income to average net assets+ 1.62% 1.21% Portfolio turnover rate 11% 10% Net assets, end of period (in thousands) $462,572 $487,357 Ratios with reduction for fees paid indirectly: Net expenses 0.74% 0.70% Net investment income 1.62% 1.21% ==================================================================================== Year Ended Year Ended Year Ended 12/31/06 12/31/05 12/31/04 Class Y Net asset value, beginning of period $ 44.31 $ 42.16 $ 38.09 - -------------------------------------------------------------------------------------------------- Increase from investment operations: Net investment income $ 0.60 $ 0.58 $ 0.52 Net realized and unrealized gain (loss) on investments 6.77 2.28 4.06 - -------------------------------------------------------------------------------------------------- Net increase (decrease) from investment operations $ 7.37 $ 2.86 $ 4.58 Distributions to shareowners: Net investment income (0.62) (0.57) (0.51) Net realized gain (2.83) (0.14) -- - -------------------------------------------------------------------------------------------------- Net increase (decrease) in net asset value $ 3.92 $ 2.15 $ 4.07 - -------------------------------------------------------------------------------------------------- Net asset value, end of period $ 48.23 $ 44.31 $ 42.16 ================================================================================================== Total return* 16.88% 6.83% 12.15% Ratio of net expenses to average net assets+ 0.70% 0.65% 0.61% Ratio of net investment income to average net assets+ 1.31% 1.31% 1.34% Portfolio turnover rate 9% 13% 14% Net assets, end of period (in thousands) $401,391 $269,333 $155,647 Ratios with reduction for fees paid indirectly: Net expenses 0.70% 0.65% 0.61% Net investment income 1.31% 1.31% 1.34% ================================================================================================== * 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 each end of each period. + Ratio with no reduction for fees paid indirectly. The accompanying notes are an integral part of these financial statements. Pioneer Fund | Annual Report | 12/31/08 35 Financial Highlights (continued) Year Ended 4/30/07 to 12/31/08 12/31/07 (a) Class Z Net asset value, beginning of period $ 46.41 $ 50.61 - ----------------------------------------------------------------------------------------- Increase (decrease) from investment operations: Net investment income $ 0.63 $ 0.42 Net realized and unrealized loss on investments (16.36) (0.58) - ----------------------------------------------------------------------------------------- Net decrease from investment operations $ (15.73) $ (0.16) Distributions to shareowners: Net investment income (0.62) (0.47) Net realized gain (0.86) (3.57) - ----------------------------------------------------------------------------------------- Net decrease in net asset value $ (17.21) $ (4.20) - ----------------------------------------------------------------------------------------- Net asset value, end of period $ 29.20 $ 46.41 ========================================================================================= Total return* (34.06)% (0.70)%(b) Ratio of net expenses to average net assets+ 0.74% 0.70%** Ratio of net investment income to average net assets+ 1.57% 1.25%** Portfolio turnover rate 11% 10% Net assets, end of period (in thousands) $ 58 $ 92 Ratios with reduction for fees paid indirectly: Net expenses 0.74% 0.70%** Net investment income 1.57% 1.25%** ========================================================================================= (a) Class Z shares were first publicly offered on April 30, 2007. (b) Not Annualized. * 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 each end of each period. ** Annualized. + Ratio with no reduction for fees paid indirectly. The accompanying notes are an integral part of these financial statements. 36 Pioneer Fund | Annual Report | 12/31/08 Notes to Financial Statements | 12/31/08 1. Organization and Significant Accounting Policies Pioneer Fund (the Fund) is a Delaware statutory trust registered under the Investment Company Act of 1940 as a diversified, open-end management investment company. The investment objective of the Fund is to provide reasonable income and capital growth. The Fund offers six classes of shares designated as Class A, Class B, Class C, Class R, Class Y and Class Z shares. Class Z shares were first publicly offered on April 30, 2007. 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 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 by each class. The Amended and Restated Declaration of Trust of the Fund gives the Board the flexibility to specify either per share voting or dollar-weighted voting when submitting matters for shareholder approval. Under per share voting, each share of a class of the Fund is entitled to one vote. Under dollar-weighted voting, a shareholder's voting power is determined not by the number of shares owned, but by the dollar value of the shares on the record date. Share classes have 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 and Class Z shares. Class B shares convert to Class A shares approximately eight years after the date of purchase. The Fund's financial statements have been prepared in conformity with U.S. generally accepted accounting principles, that require the management of the Fund to, among other things, make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of income, expenses and gains and losses on investments during the reporting year. Actual results could differ from those estimates. At times, the Fund's investments may represent industries or industry sectors that are interrelated or have common risks, making it more susceptible to any economic, political, or regulatory developments or other risks affecting those industries and sectors. The Fund's prospectuses contain unaudited information regarding the fund's principal risks. Please refer to those documents when considering the Fund's principal risks. Pioneer Fund | Annual Report | 12/31/08 37 The following is a summary of significant accounting policies followed by the Fund in the preparation of its financial statements, which are consistent with those policies generally accepted in the investment company industry: A. Security Valuation Security transactions are recorded as of trade date. The net asset value is computed once daily, on each day the New York Stock Exchange (NYSE) is open, as of the close of regular trading on the NYSE. In computing the net asset value, securities are valued at the last sale price on the principal exchange where they are traded. Securities that have not traded on the date of valuation, or securities for which sale prices are not generally reported, are valued at the mean between the last bid and asked prices. Securities for which market quotations are not readily available are valued using fair value methods pursuant to procedures adopted by the Board of Trustees. Trading in foreign securities is substantially completed each day at various times prior to the close of the NYSE. The values of such securities used in computing the net asset value of the Fund's shares are determined as of such times. The Fund may also use fair value methods to value a security, including a non-U.S. security, when the closing market price on the principal exchange where the security is traded no longer reflects the value of the security. At December 31, 2008 there were no securities that were valued using fair value methods. Temporary cash investments are valued at cost which approximates market value. Dividend income is recorded on the ex-dividend date except that certain dividends from foreign securities where the ex-dividend date may have passed are recorded as soon as the Fund becomes aware of the ex-dividend data in the exercise of reasonable diligence. Interest income is recorded on the accrual basis. Dividend and interest income are reported net of unrecoverable foreign taxes withheld at the applicable country rates. Gains and losses on sales of investments are calculated on the identified cost method for both financial reporting and federal income tax purposes. B. 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 38 Pioneer Fund | Annual Report | 12/31/08 changes in market prices on those securities but are included with the net realized and unrealized gain or loss on investments. C. Federal Income Taxes It is the Fund's policy to comply with the requirements of the Internal Revenue Code applicable to regulated investment companies and to distribute all of its taxable income and net realized capital gains, if any, to its shareowners. Therefore, no federal income tax provision is required. Tax years for the prior three fiscal years remain subject to examination by tax authorities. The amounts and characterizations of distributions to shareowners for financial reporting purposes are determined in accordance with federal income tax rules. Therefore, the sources of the Fund's distributions may be shown in the accompanying financial statements as from or in excess of net investment income or as from net realized gain on investment transactions, or as from paid-in capital, depending on the type of book/tax differences that may exist. The Fund has elected to defer $44,303,195 of capital losses recognized between November 1, 2008 and December 31, 2008 to its fiscal year ending December 31, 2009. At December 31, 2008, the Fund had a net capital loss carryforward of $121,965,319, which will expire in 2016 if not utilized. At December 31, 2008, the Fund has reclassified $494,744 to decrease accumulated net realized loss on investments and foreign currency transactions, $4,781 to decrease accumulated net investment loss and $499,525 to decrease paid-in capital, to reflect permanent book/tax differences. The reclassification has no impact on the net assets of the Fund and presents the Fund's capital accounts on a tax basis. The tax character of distributions paid during the years ended December 31, 2008 and December 31, 2007 was as follows: 2008 2007 Distributions paid from: Ordinary income $ 68,503,229 $ 61,242,909 Long-term capital gain 132,266,933 545,354,822 ---------------------------------------------------------- Total $200,770,162 $606,597,731 ========================================================== Pioneer Fund | Annual Report | 12/31/08 39 The following shows the components of distributable earnings on a federal income tax basis at December 31, 2008: 2008 Distributable earnings: Capital loss carryforward $(121,965,319) Current year post-October loss deferred (44,303,195) Unrealized appreciation 861,475,630 --------------------------------------------------------- Total $ 695,207,116 ========================================================== The difference between book-basis and tax-basis unrealized appreciation is attributable to the tax deferral of losses on wash sales. D. Fund Shares The Fund records sales and repurchases of its shares as of trade date. Pioneer Funds Distributor, Inc. (PFD), the principal underwriter for the Fund and a wholly owned indirect subsidiary of UniCredit S.p.A. (UniCredit), earned $852,769 in underwriting commissions on the sale of Class A shares during the year ended December 31, 2008. E. 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 their 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, Class B, Class C, and Class R shares of the Fund, respectively (see Note 4). Class Y and Class Z shares are not subject to a distribution plan. Shareowners of each class participate in all expenses and fees paid to the transfer agent, Pioneer Investment Management Shareholder Services, Inc. (PIMSS), for its services, which are allocated 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 Class A, Class B, Class C, and Class R shares can bear different transfer agent and distribution expense rates. F. Securities Lending The Fund lends securities in its portfolio to certain broker-dealers or other institutional investors. When entering into a securities loan transaction, the Fund typically receives cash collateral from the borrower equal to at least the 40 Pioneer Fund | Annual Report | 12/31/08 value of the securities loaned, which is invested in temporary cash investments. Credit Suisse, New York Branch, as the Fund's security lending agent, manages the Fund's securities lending collateral. The income earned on the investment of collateral is shared with the borrower and the lending agent in payment of any rebate due to the borrower with respect to the securities loan, and in compensation for the lending agent's services to the Fund. The Fund also continues to receive interest or payments in lieu of dividends on the securities loaned. Gain or loss on the value of the loaned securities that may occur during the term of the loan will be for the account of the Fund. The amount of the collateral is required to be adjusted daily to reflect any price fluctuation in the value of the loaned securities. The Fund has the right, under the lending agreement, to terminate the loan and recover the securities from the borrower with prior notice. The Fund will be required to return the cash collateral to the borrower and could suffer a loss if the value of the collateral, as invested, has declined. G. Repurchase Agreements With respect to repurchase agreements entered into by the Fund, the value of the underlying securities (collateral), including accrued interest, is required to be at least equal to or in excess of the value of the repurchase agreement. The collateral for all repurchase agreements is held in safekeeping in the customer-only account of the Fund's custodian or subcustodians. The Fund's investment adviser, Pioneer Investment Management, Inc. (PIM), is responsible for determining that the value of the collateral remains at least equal to the repurchase price. 2. Management Agreement PIM, a wholly owned indirect subsidiary of UniCredit, manages the Fund's portfolio. PIM receives a basic fee that is equal to 0.60% of the Fund's average daily net assets up to $7.5 billion, 0.575% on the next $2.5 billion and 0.550% on the excess over $10 billion. The basic fee can increase or decrease by a maximum of 0.10% based on the investment performance of the Fund's Class A shares as compared to the Standard and Poor's 500 Index. The performance comparison is made for a rolling 36-month period. In addition, the fee is further limited to a maximum annualized rate adjustment of +0.10%. For year ended December 31, 2008, the aggregate performance adjustment resulted in an increase to the basic fee of $3,013,393. For the year ended December 31, 2008, the net management fee was equivalent to 0.64% of the Fund's average daily net assets. 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. Included in "Due to Affiliates" reflected on the Statement of Assets and Liabilities is $85,534 in management fees, Pioneer Fund | Annual Report | 12/31/08 41 administrative costs and certain other fees payable to PIM at December 31, 2008. 3. Transfer Agent PIMSS, a wholly owned indirect subsidiary of UniCredit, provides substantially all transfer agent and shareowner services to the Fund at negotiated rates. In addition, the Fund reimbursed PIMSS for out-of-pocket expenses related to shareholder communications activities such as proxy and statement mailings, outgoing phone calls and omnibus relationship contracts. For the year ended December 31, 2008, such out of pocket expenses by class of shares were as follows: Shareholder Communications: Class A $2,483,765 Class B 169,663 Class C 341,049 Class R 130,370 Class Y 85,311 Class Z 13 --------------------------------------- Total: $3,210,171 ======================================= Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $1,145,810 in transfer agent fees and shareholder communications expense payable to PIMSS at December 31, 2008. 4. Distribution and Service Plans The Fund adopted a Distribution Plan pursuant to Rule 12b-1 of the Investment Company Act of 1940 with respect to its Class A, Class B, Class C and Class R shares. Pursuant to the Plan, the Fund pays PFD 0.25% of the average daily net assets attributable to Class A shares as compensation for personal services and/or account maintenance services or distribution services with regard to Class A shares. Pursuant to the Plan, the Fund pays PFD 1.00% of the average daily net assets attributable to Class B and Class C shares. The fee for Class B and 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 B and Class C shares. Pursuant to the Plan, the Fund pays PFD 0.50% of the average daily net assets attributable to Class R shares for distribution services. Prior to February 1, 2008, PFD was reimbursed under the Distribution Plan for distribution expenses in an amount of up to 0.25% of the average daily net assets attributable to Class A shares. Included in "Due to affiliates" reflected on the Statement of Assets and Liabilities is $90,692 in distribution fees payable to PFD at December 31, 2008. 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 42 Pioneer Fund | Annual Report | 12/31/08 to provide certain services to retirement plans or plan participants holding shares of the Fund a service fee of up to 0.25% 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 R, Class Y and Class Z 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 18 months of purchase. Class B shares that are redeemed within five years of purchase are subject to a CDSC at declining rates beginning at 4.00%, based on the lower of cost or market value of shares being redeemed. Redemptions of Class C shares within one year of purchase are subject to a CDSC of 1.00%, based on the lower of cost or market value of shares being redeemed. There is no CDSC for Class R, Class Y or Class Z shares. Proceeds from the CDSCs are paid to PFD. For year ended December 31, 2008, CDSCs in the amount of $380,399 were paid to PFD. 5. Expense Offset Arrangements The Fund has entered into certain expense offset arrangements with PIMSS that may result in reduction in the Fund's transfer agent fees and expenses due to interest earned on cash held by PIMSS. For the year ended December 31, 2008, the Fund's expenses were reduced by $270,760 under these arrangements. 6. Affiliated Companies The Fund's investments in certain companies may exceed 5% of the outstanding voting stock. Such companies are deemed affiliates of the Fund for financial reporting purposes. The following summarizes transactions with affiliates of the Fund for the year ended December 31, 2008: Beginning Ending Balance Purchases Sales Dividend Balance Affiliates (shares) (shares) (shares) Income (shares) Value John Wiley and Sons 3,494,400 -- -- $1,747,200 3,494,400 $124,330,752 7. New Pronouncement In March 2008, Statement of Financial Accounting Standards No. 161, Disclosures about Derivative Instruments and Hedging Activities ("SFAS 161"), was issued and is effective for fiscal years beginning after November 15, 2008. SFAS 161 requires enhanced disclosures about an entity's derivative and hedging activities. Management is currently evaluating the impact the adoption of SFAS 161 will have on the Fund's financial statement disclosures. Pioneer Fund | Annual Report | 12/31/08 43 Report of Independent Registered Public Accounting Firm To the Board of Trustees and Shareowners of Pioneer Fund: - -------------------------------------------------------------------------------- We have audited the accompanying statement of assets and liabilities of Pioneer Fund (the "Fund"), including the schedule of investments, as of December 31, 2008, and the related statement of operations for the year then ended, the statements of changes in net assets for each of the two years in the period then ended, and the financial highlights for each of the periods indicated therein. These financial statements and financial highlights are the responsibility of the Fund's management. Our responsibility is to express an opinion on these financial statements and financial highlights based on our audits. We conducted our audits in accordance with the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements and financial highlights are free of material misstatement. We were not engaged to perform an audit of the Fund's internal control over financial reporting. Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Fund's internal control over financial reporting. Accordingly, we express no such opinion. An audit also includes examining, on a test basis, evidence supporting the amounts and disclosures in the financial statements and financial highlights, assessing the accounting principles used and significant estimates made by management, and evaluating the overall financial statement presentation. Our procedures included confirmation of securities owned as of December 31, 2008, by correspondence with the custodian and brokers or by other appropriate auditing procedures where replies from brokers were not received. We believe that our audits provide a reasonable basis for our opinion. In our opinion, the financial statements and financial highlights referred to above present fairly, in all material respects, the financial position of Pioneer Fund at December 31, 2008, the results of its operations for the year then ended, the changes in its net assets for each of the two years in the period then ended, and financial highlights for each of the periods indicated therein, in conformity with U.S. generally accepted accounting principles. /s/Ernst & Young LLP Boston, Massachusetts February 18, 2009 44 Pioneer Fund | Annual Report | 12/31/08 Trustees, Officers and Service Providers Investment Adviser Pioneer Investment Management, Inc. Custodian Brown Brothers Harriman & Co. Independent Registered Public Accounting Firm Ernst & Young LLP Principal Underwriter Pioneer Funds Distributor, Inc. Legal Counsel Bingham McCutchen LLP Shareowner Services and Transfer Agent Pioneer Investment Management Shareholder Services, Inc. Proxy Voting Policies and Procedures of the Fund are available without charge, upon request, by calling our toll free number (1-800-225-6292). Information regarding how the Fund voted proxies relating to portfolio securities during the most recent 12-month period ended June 30 is publicly available to shareowners at www.pioneerinvestments.com. This information is also available on the Securities and Exchange Commission's web site at http://www.sec.gov. Trustees and Officers The Board of Trustees provides broad supervision over the Fund's affairs. The officers of the Fund are responsible for the Fund's operations. The Trustees and officers are listed below, together with their principal occupations during the past five years. Trustees who are interested persons of the Fund within the meaning of the 1940 Act are referred to as Interested Trustees. Trustees who are not interested persons of the Fund are referred to as Independent Trustees. Each of the Trustees serves as a trustee of each of the 76 U.S. registered investment portfolios for which Pioneer serves as investment adviser (the "Pioneer Funds"). The address for all Trustees and all officers of the Fund is 60 State Street, Boston, Massachusetts 02109. Pioneer Fund | Annual Report | 12/31/08 45 Interested Trustees Position Held Length of Service Name and Age with the Fund and Term of Office John F. Cogan, Jr. (82)* Chairman of the Board, Trustee since 1982. Trustee and President Serves until a successor trustee is elected or earlier retirement or removal. - ------------------------------------------------------------------------------ Daniel K. Kingsbury (50)* Trustee and Executive Trustee since 2008. Vice President Serves until a successor trustee is elected or earlier retirement or removal. - ------------------------------------------------------------------------------ * Mr. Cogan and Mr. Kingsbury are Interested Trustees because they are officers or directors of the Fund's investment adviser and certain of its affiliates. Interested Trustees Other Directorships Name and Age Principal Occupation During Past Five Years Held by this Trustee John F. Cogan, Jr. (82)* Deputy Chairman and a Director of Pioneer Global Asset None Management S.p.A. ("PGAM"); Non-Executive Chairman and a Director of Pioneer Investment Management USA Inc. ("PIM-USA"); Chairman and a Director of Pioneer; Chairman and Director of Pioneer Institutional Asset Management, Inc. (since 2006); Director of Pioneer Alternative Investment Management Limited (Dublin); President and a Director of Pioneer Alternative Investment Management (Bermuda) Limited and affiliated funds; Director of PIOGLOBAL Real Estate Investment Fund (Russia) (until June 2006); Director of Nano-C, Inc. (since 2003); Director of Cole Management Inc. (since 2004); Director of Fiduciary Counseling, Inc.; President and Director of Pioneer Funds Distributor, Inc. ("PFD") (until May 2006); President of all of the Pioneer Funds; and Of Counsel, Wilmer Cutler Pickering Hale and Dorr LLP - -------------------------------------------------------------------------------------------------------------------- Daniel K. Kingsbury (50)* Director, CEO and President of Pioneer Investment Management None USA Inc. (since February 2007); Director and President of Pioneer Investment Management, Inc. and Pioneer Institutional Asset Management, Inc. (since February 2007); Executive Vice President of all of the Pioneer Funds (since March 2007); Director of Pioneer Global Asset Management S.p.A. (since April 2007); Head of New Markets Division, Pioneer Global Asset Management S.p.A. (2000 - 2007) - -------------------------------------------------------------------------------------------------------------------- * Mr. Cogan and Mr. Kingsbury are Interested Trustees because they are officers or directors of the Fund's investment adviser and certain of its affiliates. 46 Pioneer Fund | Annual Report | 12/31/08 Independent Trustees Position Held Length of Service Name and Age with the Fund and Term of Office David R. Bock (65) Trustee Trustee since 2005. Serves until a successor trustee is elected or earlier retirement or removal. - ---------------------------------------------------------------------------------------------- Mary K. Bush (60) Trustee Trustee since 1997. Serves until a successor trustee is elected or earlier retirement or removal. - ---------------------------------------------------------------------------------------------- Independent Trustees Other Directorships Name and Age Principal Occupation During Past Five Years Held by this Trustee David R. Bock (65) Executive Vice President and Chief Financial Officer, I-trax, Inc. Director of Enterprise (publicly traded health care services company) (2004 - 2007); Community Investment, Inc. Partner, Federal City Capital Advisors (boutique merchant bank) (privately-held affordable (1997 to 2004 and 2008 - present); and Executive Vice housing finance company); President and Chief Financial Officer, Pedestal Inc. and Director of New York (internet-based mortgage trading company) (2000 - 2002) Mortgage Trust (publicly traded mortgage REIT) - ------------------------------------------------------------------------------------------------------------------------------------ Mary K. Bush (60) President, Bush International, LLC (international financial Director of Marriott International, advisory firm) Inc.; Director of Discover Financial Services (credit card issuer and electronic payment services); Director of Briggs & Stratton Co. (engine manufacturer); Director of UAL Corporation (airline holding company); Director of Mantech International Corporation (national security, defense, and intelligence technology firm); and Member, Board of Governors, Investment Company Institute - ------------------------------------------------------------------------------------------------------------------------------------ Pioneer Fund | Annual Report | 12/31/08 47 Independent Trustees (continued) Position Held Length of Service Name and Age with the Fund and Term of Office Benjamin M. Friedman (64) Trustee Trustee since 2008. Serves until a successor trustee is elected or earlier retirement or removal - ---------------------------------------------------------------------------------------- Margaret B.W. Graham (61) Trustee Trustee since 1990. Serves until a successor trustee is elected or earlier retirement or removal. - ---------------------------------------------------------------------------------------- Thomas J. Perna (58) Trustee Trustee since 2006. Serves until a successor trustee is elected or earlier retirement or removal. - ---------------------------------------------------------------------------------------- Marguerite A. Piret (60) Trustee Trustee since 1982. Serves until a successor trustee is elected or earlier retirement or removal. - ---------------------------------------------------------------------------------------- Stephen K. West (80) Trustee Trustee since 2008. Serves until a successor trustee is elected or earlier retirement or removal. - ---------------------------------------------------------------------------------------- Other Directorships Name and Age Principal Occupation During Past Five Years Held by this Trustee Benjamin M. Friedman (64) Professor, Harvard University Trustee, Mellon Institutional Funds Investment Trust and Mellon Institutional Funds Master Portfolio (oversees 17 portfolios in fund complex) - ----------------------------------------------------------------------------------------------------------------------------- Margaret B.W. Graham (61) Founding Director, Vice President and Corporate Secretary, The None Winthrop Group, Inc. (consulting firm); and Desautels Faculty of Management, McGill University - ----------------------------------------------------------------------------------------------------------------------------- Thomas J. Perna (58) Chief Executive Officer, Quadriserv, Inc. (technology products for None securities lending industry) (2008 - present); Private investor (2004 - 2008); and Senior Executive Vice President, The Bank of New York (financial and securities services) (1986 - 2004) - ----------------------------------------------------------------------------------------------------------------------------- Marguerite A. Piret (60) President and Chief Executive Officer, Newbury, Piret & Company, Director of New America Inc. (investment banking firm) High Income Fund, Inc. (closed-end investment company) - ----------------------------------------------------------------------------------------------------------------------------- Stephen K. West (80) Senior Counsel, Sullivan & Cromwell LLP (law firm) Director, The Swiss Helvetia Fund, Inc. (closed-end investment company) - ----------------------------------------------------------------------------------------------------------------------------- 48 Pioneer Fund | Annual Report | 12/31/08 Fund Officers Position Held Length of Service Name and Age with the Fund and Term of Office Dorothy E. Bourassa (60) Secretary Since 2000. Serves at the discretion of the Board - -------------------------------------------------------------------------- Christopher J. Kelley (44) Assistant Secretary Since 2003. Serves at the discretion of the Board - -------------------------------------------------------------------------- Mark E. Bradley (49) Treasurer Since 2008. Serves at the discretion of the Board - -------------------------------------------------------------------------- Luis I. Presutti (43) Assistant Treasurer Since 2000. Serves at the discretion of the Board - -------------------------------------------------------------------------- Gary Sullivan (50) Assistant Treasurer Since 2002. Serves at the discretion of the Board - -------------------------------------------------------------------------- Fund Officers Other Directorships Name and Age Principal Occupation During Past Five Years Held by this Officer Dorothy E. Bourassa (60) Secretary of PIM-USA; Senior Vice President - Legal of Pioneer; None Secretary/Clerk of most of PIM-USA's subsidiaries; and Secretary of all of the Pioneer Funds since September 2003 (Assistant Secretary from November 2000 to September 2003) - -------------------------------------------------------------------------------------------------------------------- Christopher J. Kelley (44) Associate General Counsel of Pioneer since January 2008 and None Assistant Secretary of all of the Pioneer Funds since September 2003; Vice President and Senior Counsel of Pioneer from July 2002 to December 2007 - -------------------------------------------------------------------------------------------------------------------- Mark E. Bradley (49) Vice President - Fund Accounting, Administration and Controllership None ship Services of Pioneer; and Treasurer of all of the Pioneer Funds since March 2008; Deputy Treasurer of Pioneer from March 2004 to February 2008; Assistant Treasurer of all of the Pioneer Funds from March 2004 to February 2008; and Treasurer and Senior Vice President, CDC IXIS Asset Management Services from 2002 to 2003 - -------------------------------------------------------------------------------------------------------------------- Luis I. Presutti (43) Assistant Vice President - Fund Accounting, Administration and None Controllership Services of Pioneer; and Assistant Treasurer of all of the Pioneer Funds - -------------------------------------------------------------------------------------------------------------------- Gary Sullivan (50) Fund Accounting Manager - Fund Accounting, Administration and None Controllership Services of Pioneer; and Assistant Treasurer of all of the Pioneer Funds - -------------------------------------------------------------------------------------------------------------------- Pioneer Fund | Annual Report | 12/31/08 49 Fund Officers (continued) Position Held Length of Service Name and Age with the Fund and Term of Office Katherine Kim Sullivan (35) Assistant Treasurer Since 2003. Serves at the discretion of the Board - -------------------------------------------------------------------------- Teri W. Anderholm (49) Chief Compliance Officer Since 2007. Serves at the discretion of the Board - -------------------------------------------------------------------------- Other Directorships Name and Age Principal Occupation During Past Five Years Held by this Officer Katherine Kim Sullivan (35) Fund Administration Manager - Fund Accounting, Administration None and Controllership Services since June 2003 and Assistant Treasurer of all of the Pioneer Funds since September 2003; Assistant Vice President - Mutual Fund Operations of State Street Corporation from June 2002 to June 2003 (formerly Deutsche Bank Asset Management) - -------------------------------------------------------------------------------------------------------------------- Teri W. Anderholm (49) Chief Compliance Officer of Pioneer since December 2006 and None of all the Pioneer Funds since January 2007; Vice President and Compliance Officer, MFS Investment Management (August 2005 to December 2006); Consultant, Fidelity Investments (February 2005 to July 2005); Independent Consultant (July 1997 to February 2005) - -------------------------------------------------------------------------------------------------------------------- 50 Pioneer Fund | Annual Report | 12/31/08 This page for your notes. Pioneer Fund | Annual Report | 12/31/08 51 This page for your notes. 52 Pioneer Fund | Annual Report | 12/31/08 How to Contact Pioneer We are pleased to offer a variety of convenient ways for you to contact us for assistance or information. Call us for: - -------------------------------------------------------------------------------- Account Information, including existing accounts, new accounts, prospectuses, applications and service forms 1-800-225-6292 FactFone(SM) for automated fund yields, prices, account information and transactions 1-800-225-4321 Retirement plans information 1-800-622-0176 Telecommunications Device for the Deaf (TDD) 1-800-225-1997 Write to us: - -------------------------------------------------------------------------------- PIMSS, Inc. P.O. Box 55014 Boston, Massachusetts 02205-5014 Our toll-free fax 1-800-225-4240 Our internet e-mail address ask.pioneer@pioneerinvestments.com (for general questions about Pioneer only) Visit our web site: pioneerinvestments.com This report must be 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.