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Filed Pursuant to Rule 497(e)
Registration File No.: 333-29721
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER S&P 500 INDEX FUND
DATED OCTOBER 30, 1998
The sixth paragraph of the section entitled "The Fund and Its Management"
in the above Prospectus is revised to reflect that, effective May 1, 1999, the
Trustees of the Fund have amended the Fund's Investment Management Agreement to
reduce the compensation received by the Investment Manager under the Agreement
for assets exceeding $1.5 billion, so that the compensation under the Agreement
is calculated daily by applying the following annual rates to the Fund's net
assets determined as of the close of each business day: 0.40% of the portion of
daily net assets not exceeding $1.5 billion; 0.375% of the next $1.5 billion;
and 0.35% of the portion of daily net assets exceeding $3 billion.
May 1, 1999
