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Filed Pursuant to Rule 497(e)
Registration File No.: 2-81151
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER
DEVELOPING GROWTH SECURITIES TRUST
DATED NOVEMBER 29, 1999
The second paragraph under the section of the Prospectus entitled "FUND
MANAGEMENT" is hereby replaced by the following:
The Fund's portfolio is managed within the Investment Manager's Growth
Group. Armon Bar-Tur, a Vice President of the Investment Manager, has been
the Fund's primary portfolio manager since July 1999. Mr. Bar-Tur has been
a portfolio manager with the Investment Manager since October 1996, prior
to which time he was a research analyst with Merrill Lynch Asset
Management. Co-management has been provided by John Roscoe, a Vice
President of the Investment Manager, since May 2000. Mr. Roscoe has been a
portfolio manager with the Investment Manager since December 1997, prior
to which time he was an equity analyst at Rockefeller and Company, Inc.
May 22, 2000
