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Filed Pursuant to Rule 497(e)
Registration File No.: 2-81151
811-3639
SUPPLEMENT TO THE PROSPECTUS OF
MORGAN STANLEY DEAN WITTER
DEVELOPING GROWTH SECURITIES TRUST
DATED NOVEMBER 29, 2000
The fifth sentence under the section of the Prospectus titled "PRINCIPAL
INVESTMENT STRATEGIES" is hereby replaced by the following:
The Investment Manager focuses its securities selection upon a diversified
group of emerging growth companies that it believes have prospects of
achieving significant profit gains.
In addition, the second paragraph under the section of the Prospectus
titled "FUND MANAGEMENT" is hereby replaced by the following:
The Fund's portfolio is managed within the Investment Manager's Growth
Group. Arden C. Armstrong, a Managing Director of the Investment Manager
as well as a Managing Director of Miller Anderson & Sherrerd, LLP ("MAS"),
an affiliate of the Investment Manager, has been the Fund's primary
portfolio manager since January 2001. Ms. Armstrong has been managing
portfolios for MAS and investment advisory affiliates of MAS for over five
years. 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.
January 8, 2001
