EXHIBIT 4-ss


                                AMENDMENT NO. 1
                                     TO THE
                                TRUST AGREEMENT
                                       OF
                             MSDW CAPITAL TRUST III

         This Amendment No. 1 to the Trust Agreement of MSDW Capital Trust III
(the "Trust"), dated as of September 24, 2001 (this "Amendment"), is made and
entered into among Morgan Stanley Dean Witter & Co., a Delaware corporation, as
depositor (the "Depositor"), The Bank of New York (Delaware), a Delaware
banking corporation, as Delaware Trustee (the "Delaware Trustee"), The Bank of
New York, a New York banking corporation, as property trustee (the "Property
Trustee" and, together with the Delaware Trustee, the "Trustees"), and
Alexander C. Frank and Debra M. Aaron, individuals, as administrators
(together, the "Administrators").

                              W I T N E S S E T H
                              -------------------

         WHEREAS, the Trust is a Delaware business trust that was created under
Chapter 38 of Title 12 of the Delaware Code, 12 Del. C. ss. 3801, et seq. (the
"Act") pursuant to (i) the Trust Agreement of the Trust, dated as of February
12, 1998 (the "Trust Agreement"), and (ii) the Certificate of Trust of the
Trust, dated February 12, 1998, as filed with the office of the Secretary of
State of the State of Delaware (the "Secretary of State") on February 12, 1998;
and

         WHEREAS, the Delaware Trustee will file the Certificate of Amendment
of Certificate of Trust of the Trust, dated as of September 24, 2001 (the
"Certificate of Amendment"), with the Secretary of State on September 24, 2001;
and

         WHEREAS, the Depositor, the Trustees and the Administrators desire to
amend the Trust Agreement.

         NOW, THEREFORE, in consideration of the mutual promises and
obligations contained herein, the parties hereto, intending to be legally
bound, hereby agree as follows:

I.       AMENDMENTS.
         ----------

         A. The Trust Agreement is hereby amended to reflect that the name of
the Trust has been changed to "Morgan Stanley Capital Trust III" pursuant to
the Certificate of Amendment.

         B. Section 4 of the Trust  Agreement is hereby  deleted in its
entirety and it shall be replaced with the following:

         "4. The Depositor, as the depositor of the Issuer Trust, is hereby
         authorized and appointed as the Issuer Trust's and the Issuer
         Trustees' true and lawful attorney-in-fact and agent (i) to file with
         the Securities and Exchange Commission (the "Commission") and to
         execute, in the case of the 1933 Act Registration Statement and 1934
         Act Registration Statement (each as herein defined) and any and all
         amendments thereto, including pre-effective and post-effective
         amendments, on







         behalf of the Issuer Trust, (a) a Registration Statement (the "1933
         Act Registration Statement"), including pre-effective or
         post-effective amendments thereto, with all exhibits thereto, and any
         other documents that may be required in connection therewith, relating
         to the registration under the Securities Act of 1933, as amended (the
         "1933 Act"), of the Capital or Preferred Securities of the Issuer
         Trust, (b) any preliminary prospectus or prospectus or supplement
         thereto relating to the Capital or Preferred Securities required to be
         filed pursuant to the 1933 Act, and (c) a Registration Statement on
         Form 8-A or other appropriate form (the "1934 Act Registration
         Statement"), including all pre-effective and post-effective amendments
         thereto, with all exhibits thereto, and any other documents that may
         be required in connection therewith, relating to the registration of
         the Capital or Preferred Securities of the Issuer Trust under the
         Securities Exchange Act of 1934, as amended; (ii) to file with the New
         York Stock Exchange, Inc., the American Stock Exchange LLC, The London
         Stock Exchange plc, The Luxembourg Stock Exchange, The Paris Bourse or
         other stock exchange or securities market, or the National Association
         of Securities Dealers (the "NASD"), and execute and verify on behalf
         of the Issuer Trust a listing application and all other applications,
         statements, certificates, agreements and other instruments, under seal
         or otherwise, as shall be necessary or desirable, and do or cause to
         be done all such acts and things in the name of and on behalf of the
         Issuer Trust to meet the requirements of any such stock exchange,
         securities market or the NASD's Nasdaq National Market, or to appear
         before the appropriate representatives of committees of any such stock
         exchange or securities market, in order to cause the Capital or
         Preferred Securities to be listed on any such stock exchange or
         securities market; (iii) to file, execute and verify on behalf of the
         Issuer Trust such applications, reports, surety bonds, irrevocable
         consents, appointments of attorney for service of process and other
         papers and documents as shall be necessary or desirable to register or
         qualify the Capital or Preferred Securities for offer and sale under
         the securities or "Blue Sky" laws of the various states and
         jurisdictions of the United States or under any foreign laws or
         regulations as the Depositor, on behalf of the Issuer Trust, may deem
         necessary or desirable; and (iv) to execute, deliver and perform on
         behalf of the Issuer Trust an underwriting agreement with one or more
         underwriters relating to the offering of the Capital or Preferred
         Securities of the Issuer Trust. In the event that any filing referred
         to in clauses (i), (ii) or (iii) above is required by the rules and
         regulations of the Commission, the New York Stock Exchange or such
         other exchanges or securities markets, the NASD, or the securities or
         "Blue Sky" laws or foreign laws or regulations to be executed on
         behalf of the Issuer Trust by the Administrators, the Administrators,
         in their capacity as administrators of the Issuer Trust, are hereby
         authorized and directed to join in any such filing and to execute on
         behalf of the Issuer Trust any and all of the foregoing, it being
         understood that the Administrators, in their capacity as
         administrators of the Issuer Trust, shall not be required to join in
         any such filing or execute on behalf of the Issuer Trust any such
         document unless required by the rules and regulations of the
         Commission, the New York Stock Exchange or such other exchange or
         securities markets, the NASD, or the securities or "Blue Sky" laws or
         foreign laws or regulations."


                                      -2-





II.      MISCELLANEOUS.
         -------------

          A.  Successors and Assigns.  This  Amendment shall be binding upon,
and shall enure to the benefit of, the parties hereto and their respective
successors and assigns.

          B.  Full Force and Effect.  Except to the extent modified  hereby,
the Trust Agreement shall remain in full force and effect.

          C.  Counterparts.  This  Amendment  may be  executed in
counterparts,  all of which  together  shall constitute one agreement binding
on all parties hereto,  notwithstanding  that all such parties are not
signatories to the original or same counterpart.

          D.  Governing  Law.  This Amendment  shall be interpreted in
accordance  with the laws of the State of Delaware (without regard to conflict
of laws principles), all rights and remedies being governed by such laws.

          E.  Effectiveness of Amendment.  This Amendment shall be effective
immediately upon execution.

          F.  Capitalized  Terms.  Capitalized terms used herein and not
otherwise defined are used as defined in the Trust Agreement.


                            [SIGNATURE PAGE FOLLOWS]


                                      -3-






         IN WITNESS  WHEREOF,  the parties  hereto have caused this Amendment
to be duly executed as of the day and year first above written.

                                            MORGAN STANLEY DEAN WITTER & CO.,
                                            as Depositor


                                            By:     /s/ Alexander C. Frank
                                                -------------------------------
                                                Name:  Alexander C. Frank
                                                Title: Treasurer


                                            THE BANK OF NEW YORK (DELAWARE),
                                            as Delaware Trustee


                                            By:     /s/ William T. Lewis
                                                -------------------------------
                                                Name:  William T. Lewis
                                                Title: Senior Vice President


                                            THE BANK OF NEW YORK,
                                            as Property Trustee


                                            By:     /s/ Kisha Holder
                                                -------------------------------
                                                Name:  Kisha Holder
                                                Title: Assistant Treasurer


                                            ALEXANDER C. FRANK,
                                            as Administrator


                                            /s/ Alexander C. Frank
                                            -----------------------------------


                                            DEBRA M. AARON,
                                            as Administrator


                                            /s/ Debra M. Aaron
                                            -----------------------------------