December 28, 1998
SUPPLEMENT TO THE PROSPECTUS FOR
PIONEER BOND FUND
DATED OCTOBER 28, 1998
INVESTMENT POLICIES
The Trustees of Pioneer Bond Fund (the "Fund") have approved a change in the
Fund's policies which will allow the Fund to invest (1) at least 80% of its
total assets in debt securities issued or guaranteed by the United States
Government or its agencies or instrumentalities, debt securities (including
convertible securities) rated within the four highest grades ("investment
grade") by the major recognized bond services and comparably rated commercial
paper and cash and cash equivalents; (2) the balance (up to 20%) of its total
assets in debt securities that are rated below investment grade and in
commercial paper that is of comparable quality; and (3) up to 5% of its total
assets in equity securities. Changes to the Fund's fundamental investment
restrictions set forth in the Fund's Statement of Additional Information have
also been proposed. These changes will be submitted for shareholder approval at
a meeting scheduled to be held in April, 1999. If approved by shareholders, the
changes are expected to take effect on or as soon as possible after May 1, 1999.
There can be no assurance that these changes in investment policies and
restrictions will be approved.
The Investment Company Act of 1940 (the "1940 Act") requires that the Fund
segregate assets in connection with certain types of transactions. If the Fund
enters into a transaction requiring segregation, the custodian or Pioneer
Investment Management, Inc. ("Pioneer Investments"), the Fund's investment
adviser, will segregate liquid assets in an amount required to comply with the
1940 Act. Such segregated assets will be valued at market daily. If the
aggregate value of such segregated assets declines below the aggregate value
required to satisfy the 1940 Act, additional liquid assets will be segregated.
MANAGEMENT OF THE FUND
As of December 2, 1998, day-to-day management of the Fund is the responsibility
of a team of fixed income portfolio managers and analysts supervised by Sherman
B. Russ and Kenneth J. Taubes. Mr. Russ and Mr. Taubes are jointly responsible
for overseeing Pioneer Investments' U.S. and global fixed income team. Mr. Russ
is a senior vice president of Pioneer Investments. He joined Pioneer Investments
in 1983 and has been an investment professional since 1962. Mr. Taubes joined
Pioneer Investments as a senior vice president in September 1998 and has been an
investment professional since 1986. Prior to joining Pioneer Investments, Mr.
Taubes had served since 1991 as a senior vice president and senior portfolio
manager for several Putnam Investments institutional accounts and mutual funds.
1298-5970
(C) Pioneer Funds Distributor, Inc.
