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                 MORGAN STANLEY DEAN WITTER SELECT EQUITY TRUST
                      SELECT 5 INDUSTRIAL PORTFOLIO 2000-4
                            REFERENCE TRUST AGREEMENT

                  This Reference Trust Agreement dated June 29, 2000 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."


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              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.

              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

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              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 initial 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 Select 5 Industrial Portfolio 2000-4 (the "Select 5
         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 is 25,034 for the Select 5 Trust.

                  E. A Unit is hereby declared initially equal to 1/25,034th
         for the Select 5 Trust.

                  F. The term "In-Kind Distribution Date" shall mean August 14,
         2001.

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                  G. The term "Record Dates" shall mean March 1, 2001, June 1,
         2001, September 4, 2001 and such other date as the Depositor may
         direct.


                  H. The term "Distribution Dates" shall mean March 15, 2001,
         June 15, 2001 and on or about September 11, 2001 and such other date
         as the Depositor may direct.


                  I. The term "Termination Date" shall mean September 4, 2001.

                  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.