VANGUARD MUNICIPAL BOND FUND
MONEY MARKET PORTFOLIO
PROSPECTUS SUPPLEMENT
JULY 1, 1998
Effective July 1, 1998, the Securities and Exchange Commission has made some
changes to the federal rule that governs money market funds. One such change
adds an exception to the general rule that a money market fund may not invest
more than 5% of its total assets in the securities of a single issuer. The
exception permits a money market fund to invest up to 25% of its total assets in
the highest-quality securities of a single issuer for a period of up to three
business days. The fund manager of the Money Market Portfolio of Vanguard
Municipal Bond Fund may rely on this rule when making investment decisions.
PS95
