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MFS(R) MUNICIPAL HIGH INCOME FUND
Supplement to the Current Prospectus
The description of portfolio manager under the "Management of the Fund -
Investment Adviser" section beginning on page 11 of the Prospectus is hereby
deleted and replaced in its entirety with the following: "Michael Roberge is the
portfolio manager of the Fund. Mr. Roberge, a Vice President of the Adviser, has
been employed as a portfolio manager with the Adviser since 1996. From 1994 to
1996, he worked as a municipal credit analyst and portfolio manager with
Colonial Management Associates, Inc. Prior to 1994, he was an Assistant Vice
President and credit analyst with Moody's Investor Services."
The date of this Supplement is December 3, 1997.
