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                 MORGAN STANLEY DEAN WITTER SELECT EQUITY TRUST
                          REIT PORTFOLIO SERIES 2000-1
                            REFERENCE TRUST AGREEMENT

     This Reference Trust Agreement dated May 11, 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."

     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 2.03 is amended to add the following to the end of the first
  paragraph thereof. The number of Units may be increased through a split of the
  Units or decreased through a reverse split thereof, as directed by the
  Depositor, which revised number of Units shall be recorded by Trustee on its
  books.

     E. 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

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  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.

     F. The third through fifth paragraphs of Section 3.05 shall be amended to
  provide as follows:

     On each Distribution Date or within a reasonable period of time thereafter,
  the Trustee shall distribute by mail to each Unit Holder of record at the
  close of business on the preceding Record Date at his address appearing on
  the registration books of the Trustee such Unit Holder's income distribution,
  computed as hereinafter provided, plus such holder's pro rata share of the
  cash balance of the Principal Account, each computed as of the preceding
  Record Date; provided, however, that funds credited to the Principal Account
  in the event of the failure of consummation of a contract to purchase
  Securities pursuant to Section 2.01 hereof, funds representing the proceeds
  of the sale of Securities pursuant to Section 3.08 hereof, and funds
  representing the proceeds of the sale of Securities under Sections 5.02 or
  6.04 in excess of the amounts needed for the purposes of said Sections shall
  not be distributed until the next Distribution Date or at such earlier date as
  shall be determined by the Trustee. The Trustee shall not be required to make
  a distribution from the Principal Amount unless the cash balance on deposit
  therein available for distribution shall be sufficient to distribute at least
  $1.00 per Unit in the case of Units initially offered at approximately $1,000
  or a proportionately lower amount in the case of Units initially offered at
  less that $1,000 (e.g. $.001 per Unit in the case of Units initially offered
  at approximately $1.00).

     The Trustee shall, as of each Record Date, compute and report to the
  Depositor the per-Unit amount of the

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  monthly income distribution to be made on the next following Distribution
  Date (the "Monthly Income Distribution") by (i) estimating the annual income
  of the Trust for the ensuing twelve months (by reference to the most recent
  distributions made on Securities and any information received by the Trustee
  with respect to future dividends or other income), (ii) deducting therefrom
  the estimated costs and expenses to be incurred during the twelve-month period
  for which such income has been estimated and (iii) dividing the amount so
  obtained by the result of 12 multiplied by the number of Units outstanding on
  such Record Date. However, unless the Trustee or the Sponsor determines that
  the Monthly Income Distribution should be adjusted as provided hereafter, the
  amount of the Monthly Income Distribution shall be the amount computed by the
  Trustee on the most recent prior, or concurrently occurring, Quarterly
  Computation Date (such "Quarterly Computation Date" being the first Record
  Date and each Record Date occurring at three-month intervals thereafter).
  The Trustee will adjust the amount of the Monthly Income Distribution
  computed on each Quarterly Computation Date to reconcile, over the ensuing
  three Monthly Income Distributions, any variance between net income and
  distributions made during the preceding three months. Notwithstanding the
  preceding, the Trustee may reduce the amount of any Monthly Income
  Distribution in the event the Trustee or the Sponsor determines that such
  adjustment is necessary to avoid, or to respond to, a significant discrepancy
  between estimated and actual net income. Notwithstanding the foregoing, the
  Trustee may adjust the amount of the Monthly Income Distribution in order to
  maintain an average annual cash balance in the Income Account of $0.

     In the event the amount on deposit in the Income Account of the Trust on a
  Distribution Date is not sufficient for the payment of the amount of income to
  be distributed on the basis of the aforesaid computation, the Trustee shall
  advance out of its own funds and cause to be deposited in and credited to the
  Income Account such amount as may be required to permit payment of the income
  distribution to be made on such Distribution Date and shall be entitled to be
  reimbursed, without interest, out of the income subsequently received on the
  first Record Date following the date of such advance on which such
  reimbursement may be made without reducing the cash balance of the Income
  Account to an amount less than that required for the next ensuing
  distribution. The Trustee shall be deemed to be the beneficial owner of the
  dividends or

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  other income received by the Trust to the extent of all amounts advanced by it
  pursuant to this paragraph, and such advances shall be considered a lien on
  the Trust prior to the interest of Unit Holders.

     The amounts to be distributed to each Unit Holder shall be that per-Unit
  income distribution and pro rata share of the cash balance of the Principal
  Account of the Trust, computed as hereinabove provided, as shall be
  represented by the Units owned by such Unit Holder as evidenced by the record
  books of the Trustee as of the applicable Record Date.

     In computing the distribution to be made to any Unit Holder, fractions of
  one cent shall be omitted. After any such distribution, any cash balance
  remaining in the Income Account or the Principal Account shall be held in the
  same manner as other amounts subsequently deposited in each of such Accounts,
  respectively.

     G. Section 3.15 shall be amended by adding the following to the end
  thereof:

     The Depositor represents that the price paid by any Unit holder for Units
  acquired through reinvestment of Trust distributions will be reduced by the
  aggregate amount of unpaid deferred sales charge at the time of the purchase
  to offset any subsequent collection by the Depositor of deferred sales charge
  in respect of the Units so acquired.

                                       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
  REIT Portfolio Series 2000-1 (the "REIT" 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.

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     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 25,178 for the REIT Trust.

     E. A Unit is hereby declared initially equal to 1/25,178th for the
  REIT Trust.

     F. The term "In-Kind Distribution Date" shall mean April 18, 2002.

     G. The term "Record Date" shall mean monthly on the 1st day of each month
  beginning June 1, 2000.

     H. The term "Distribution Dates" shall mean monthly on the 15th day of each
  month beginning June 15, 2000.

     I. The term "Termination Date" shall mean May 31, 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. The Indenture is amended to provide that the period during which the
  Trustee shall liquidate the Trust Securities shall not exceed 30 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.