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MFS(R) MUNICIPAL BOND FUND
Supplement to the Current Prospectus
The description of portfolio manager under the "Management of the Fund
Investment Adviser" section is hereby revised as follows: Effective March 4,
1998, Geoffrey L. Schechter is the portfolio manager of the Fund. Mr. Schechter,
a Vice President of the Adviser, has been employed as a portfolio manager with
the Adviser since 1993. Prior to 1993, Mr. Schechter was a Senior Investment
Analyst at Liberty Mutual Insurance Company.
The date of this Supplement is March 4, 1998.
