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                 MORGAN STANLEY DEAN WITTER SELECT EQUITY TRUST
                   STRATEGIC GROWTH LARGE-CAP PORTFOLIO 2001-1
                            REFERENCE TRUST AGREEMENT


          This Reference Trust Agreement dated January 18, 2001 between DEAN
WITTER REYNOLDS INC., as Depositor, and The Chase Manhattan Bank, as Trustee,
sets forth certain provisions in full and incorporates other provisions by
reference to the document entitled "Sears Equity Investment Trust, Trust
Indenture and Agreement" dated January 22, 1991, as amended on March 16, 1993,
July 18, 1995 and December 30, 1997 (the "Basic Agreement"). Such provisions as
are incorporated by reference constitute a single instrument (the "Indenture").

                                WITNESSETH THAT:


          In consideration of the premises and of the mutual agreements herein
contained, the Depositor and the Trustee agree as follows:

                                       I.


                     STANDARD TERMS AND CONDITIONS OF TRUST


          Subject to the provisions of Part II hereof, all the provisions
contained in the Basic Agreement are herein incorporated by reference in their
entirety and shall be deemed to be a part of this instrument as fully and to the
same extent as though said provisions had been set forth in full in this
instrument except that the Basic Agreement is hereby amended in the following
manner:

          A.   Article I, Section 1.01, paragraph (29) defining "Trustee" shall
     be amended as follows:

     "'Trustee' shall mean The Chase Manhattan Bank, or any successor trustee
          appointed as hereinafter provided."

          B.   Reference to United States Trust Company of New York in its
     capacity as Trustee is replaced by The Chase Manhattan Bank throughout the
     Basic Agreement.
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          C.   Reference to "Dean Witter Select Equity Trust" is replaced by
     "Morgan Stanley Dean Witter Select Equity Trust".

          D.   Section 3.01 is amended to substitute the following:

               SECTION 3.01. INITIAL COST The costs of organizing the Trust and
          sale of the Trust Units shall, to the extent of the expenses
          reimbursable to the Depositor provided below, be borne by the Unit
          Holders, PROVIDED, HOWEVER, that, to the extent all of such costs are
          not borne by Unit Holders, the amount of such costs not borne by Unit
          Holders shall be borne by the Depositor and, PROVIDED FURTHER,
          HOWEVER, that the liability on the part of the Depositor under this
          section shall not include any fees or other expenses incurred in
          connection with the administration of the Trust subsequent to the
          deposit referred to in Section 2.01. Upon notification from the
          Depositor that the primary offering period is concluded, the Trustee
          shall withdraw from the Account or Accounts specified in the
          Prospectus or, if no Account is therein specified, from the Principal
          Account, and pay to the Depositor the Depositor's reimbursable
          expenses of organizing the Trust and sale of the Trust Units in an
          amount certified to the Trustee by the Depositor. If the balance of
          the Principal Account is insufficient to make such withdrawal, the
          Trustee shall, as directed by the Depositor, sell Securities
          identified by the Depositor, or distribute to the Depositor Securities
          having a value, as determined under Section 4.01 as of the date of
          distribution, sufficient for such reimbursement. The reimbursement
          provided for in this section shall be for the account of the
          Unitholders of record at the conclusion of the primary offering period
          and shall not be reflected in the computation of the Unit Value prior
          thereto. As used herein, the Depositor's reimbursable expenses of
          organizing the Trust and sale of the Trust Units shall include the
          cost of the initial preparation and typesetting of the registration
          statement, prospectuses (including preliminary prospectuses), the
          indenture, and other documents relating to the Trust, SEC and state
          blue sky registration fees, the cost of the ini-

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          tial valuation of the portfolio and audit of the Trust, the initial
          fees and expenses of the Trustee, and legal and other out-of-pocket
          expenses related thereto, but not including the expenses incurred in
          the printing of preliminary prospectuses and prospectuses, expenses
          incurred in the preparation and printing of brochures and other
          advertising materials and any other selling expenses. Any cash which
          the Depositor has identified as to be used for reimbursement of
          expenses pursuant to this Section shall be reserved by the Trustee
          for such purpose and shall not be subject to distribution or, unless
          the Depositor otherwise directs, used for payment of redemptions in
          excess of the per-Unit amount allocable to Units tendered for
          redemption.

                                       II.


                      SPECIAL TERMS AND CONDITIONS OF TRUST


          The following special terms and conditions are hereby agreed to:

          A.   The Trust is denominated Morgan Stanley Dean Witter Select Equity
     Trust Strategic Growth Large-Cap Portfolio 2001-1 (the "Strategic Growth
     Trust").

          B.   The publicly traded stocks listed in Schedule A hereto are those
     which, subject to the terms of this Indenture, have been or are to be
     deposited in trust under this Indenture.

          C.   The term, "Depositor" shall mean Dean Witter Reynolds Inc.

          D.   The aggregate number of Units referred to in Sections 2.03 and
     9.01 of the Basic Agreement 25,126 is for the Strategic Growth Trust.

          E.   A Unit is hereby declared initially equal to
     1/25,126th for the Strategic Growth Trust.

          F.   The term "In-Kind Distribution Date" shall mean
     April 2, 2002.
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          G.   The term "Record Dates" shall mean September 1,
     2001 and April 22, 2002 and such other date as the
     Depositor may direct.

          H.   The term "Distribution Dates" shall mean
     September 15, 2001 and on or about April 29, 2002 and
     such other date as the Depositor may direct.

          I.   The term "Termination Date" shall mean
     April 22, 2002.

          J.   The Depositor's Annual Portfolio Supervision Fee shall be a
     maximum of $0.25 per 100 Units.

          K.   The Trustee's annual fee as defined in Section 6.04 of the
     Indenture shall be $.90 per 100 Units if the greatest number of Units
     outstanding during the period is 10,000,000 or more; $.96 per 100 Units if
     the greatest number of Units outstanding during the period is between
     5,000,000 and 9,999,999; and $1.00 per 100 Units if the greatest number of
     Units outstanding during the period is 4,999,999 or less.

          L.   For a Unit Holder to receive an "in-kind" distribution during
     the life of the Trust, such Unit Holder must tender at least 25,000 Units
     for redemption. There is no minimum amount of Units that a Unit Holder must
     tender in order to receive an "in-kind" distribution on the In-Kind Date or
     in connection with a rollover.

          M.   Paragraph (b)(ii) of Section 9.03 is amended to provide that the
     period during which the Trustee shall liquidate the Trust Securities shall
     not exceed 14 business days commencing on the first business day following
     the In-Kind Date.
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                  (Signatures and acknowledgments on separate pages)
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          The Schedule of Portfolio Securities in the prospectus included in
this Registration Statement is hereby incorporated by reference herein as
Schedule A hereto.