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MFS(R) INSTITUTIONAL TRUST
MFS(R) Institutional Emerging Markets Debt Fund
SUPPLEMENT TO THE CURRENT PROSPECTUS
The description of portfolio manager under the "Management of the Funds -
Investment Adviser" section is hereby revised as follows: Effective July 24,
1998, Matthew W. Ryan and Robert J. Manning are the portfolio managers of the
above Fund. Mr. Ryan has been employed as an analyst with the Adviser since
April, 1997. From July, 1993 to March, 1997, he worked as an economist with
the U. S. Executive Director's Office of the International Monetary Fund. Mr.
Manning, a Senior Vice President of the Adviser, has been employed as a
portfolio manager by the Adviser since 1984.
The date of this Supplement is July 24, 1998.
