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                                                                   EXHIBIT 10.13



                              AMENDED AND RESTATED
                                ESCROW AGREEMENT

                                        Dated as of March 10, 2000

The Chase Manhattan Bank
450 W. 33rd Street, 15th Floor
New York, New York  10001
Attn:  Mr. Paul Gilkeson

            Re:  Morgan Stanley Dean Witter Spectrum Series
                 Escrow Account
                 ------------------------------------------

Gentlemen:

                  In accordance with arrangements made by Demeter Management
Corporation, a Delaware corporation (the "General Partner"), on behalf of Morgan
Stanley Dean Witter Spectrum Select L.P., Morgan Stanley Dean Witter Spectrum
Technical L.P., Morgan Stanley Dean Witter Spectrum Strategic L.P., Morgan
Stanley Dean Witter Spectrum Global Balanced L.P., Morgan Stanley Dean Witter
Spectrum Currency L.P. ("Spectrum Currency"), and Morgan Stanley Dean Witter
Spectrum Commodity L.P., each a Delaware limited partnership (collectively, the
"Partnerships," and each individually, a "Partnership"), and Dean Witter
Reynolds Inc., the selling agent for the Partnerships (the "Depositor"; the
Partnerships and the Depositor being herein sometimes collectively referred to
as the "Parties" or, individually, as a "Party"), the Depositor shall: (i)
deliver to you, as Escrow Agent, all subscription funds (by the direct transfer
of immediately available funds into a non-interest bearing escrow account
established by you for the Partnerships, for investment in your interest bearing
money market account) received by the Depositor from each subscriber
("Subscriber" or, collectively, the "Subscribers") during Spectrum Currency's
"initial offering period" (as such term is described in the prospectus, dated
March 6, 2000, relating to Spectrum Currency and Spectrum Commodity) and each
Partnership's "continuing offering" (as such term is described in the
Partnerships' applicable Prospectus, each dated March 6, 2000, as updated,
supplemented, and amended from time to time, the "Prospectuses") in connection
with the offering to the public of units of limited partnership interest of the
Partnerships (the "Units") and (ii) promptly transmit to the General Partner a
complete report of all funds deposited with you during the initial offering
period of Spectrum Currency and continuing offering of each Partnership. You, as
Escrow Agent, shall hold such subscription funds together with any additions,
substitutions, or other financial instruments in which such funds may be
invested or for which such funds may be exchanged (collectively referred to
herein as the "Fund"), IN ESCROW upon the following terms:

                  1. (a) Following receipt by you of written notice from the
General Partner that the General Partner has rejected a Subscriber's
subscription, in whole or in part, during either the initial offering period of
Spectrum Currency or continuing offering of each Partnership, you shall transmit
to the Depositor, as soon as practicable but in no event later than three
business days following receipt by you of such notice, the amount of such
Subscriber's subscription funds that shall as having been deposited with you
hereunder and that the General

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Partner shall have notified you have been rejected and any interest earned on
the Fund and allocated to the rejected amount of such subscription in accordance
with Section 2 hereof. You shall at the same time give notice to the Depositor
of the amount of aggregate subscription funds and/or interest so returned.

                  (b) On the second business day before the scheduled day of
each closing, the General Partner shall notify you of the portion of the Fund
that represents subscriptions to be accepted by the General Partner for each
Partnership. Upon receipt by you of joint written notice from the General
Partner and the Depositor on the date of each such closing to the effect that
all of the terms and conditions with respect to the release of subscription
funds from escrow set forth in the Prospectuses have been fulfilled, you shall
promptly pay and deliver to each of the Partnerships that portion of the Fund
specified for such Partnership in the General Partner's prior instructions
(excluding any interest earned on the Fund and funds relating to rejected
subscriptions); PROVIDED, HOWEVER, that in the case of the initial closing of
Spectrum Currency you will only pay and deliver funds to the Partnerships after
a minimum of 600,000 Units of Spectrum Currency have been subscribed for in the
aggregate and not rejected by the General Partner and a minimum amount of
$6,000,000 has cleared the U.S. banking system (the subscription for each Unit
of Spectrum Currency to be $10.00 at the initial closing of Spectrum Currency
and at each subsequent closing, if any, at 100% of the net asset value per Unit
of Spectrum Currency as of the close of business on the day of the closing).

                  (c) On the date of each closing, or as soon thereafter as
practicable, you shall transmit to the Depositor an amount representing: (i) for
each Subscriber whose subscription shall be accepted by the General Partner in
whole or in part, any interest earned on the Fund and allocated to the accepted
portion of such Subscriber's subscription in accordance with Section 2 hereof,
and (ii) for each Subscriber whose subscription shall have been rejected by the
General Partner in whole or in part but whose subscription funds shall not have
been previously returned to the Depositor by you in accordance with Section 1(a)
hereof, such Subscriber's subscription funds that shall have been deposited with
you hereunder and that shall have been rejected by the General Partner, and any
interest earned on the Fund and allocated to the rejected amount of such
subscription in accordance with Section 2 hereof. You shall at the same time
give notice to the Depositor of the aggregate amount of subscription funds
and/or interest so returned.

                  (d) Notwithstanding Section 1(a) hereof, upon receipt by you
of written notice from the General Partner that a Subscriber has been rejected
or because such Subscriber has provided bad funds in the form of a bad check,
draft, or otherwise to the Depositor, you shall transmit to the Depositor,
within three business days following receipt by you of such notice, the amount
of subscription funds deposited with you hereunder relating to that amount (the
portion of such Subscriber's subscription for which good funds have not been
provided) together with any interest earned on the Fund and allocated to such
portion of such a subscription in accordance with Section 2 hereof to the date
of such return, and shall immediately notify the General Partner of the return
of such funds.

                  2. You shall hold the Fund (including any interest earned
thereon) for the account of the Partnerships pending delivery to either the
Partnerships or the Depositor, pursuant to Paragraphs 1 or 3 hereof, as the case
may be. On each day that subscription funds are


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transferred to you hereunder in immediately available funds and receipt is
confirmed before 2:00 P.M., New York City time, you shall immediately invest
such subscription funds solely in your interest bearing money market account. If
subscription funds are transferred to you in immediately available funds and
receipt is confirmed after 2:00 P.M., New York City time, you shall so invest
such funds on the next day. Interest earned on the Fund shall be allocated by
the Depositor among the Subscribers proportionately based on (A) the amount of
their respective subscriptions on deposit in the Fund and (B) the period of time
from the date that their respective subscriptions shall have been deposited in
the Fund to the earlier of the delivery of the Fund to the Partnerships at a
closing or the Depositor in accordance with Sections 1 or 3 hereof, as the case
may be.

                  3. If, during the initial offering period of Spectrum
Currency, you are notified in writing jointly by the Parties that subscriptions
for fewer than 600,000 Units have been subscribed for and not rejected by the
General Partner, that the offering of Units has been terminated, and that no
initial closing of Spectrum Currency will be held, you shall transmit to the
Depositor, as soon as practicable but in no event later than three business days
after receipt by you of such notice, an amount representing the full amount of
all subscription funds that shall have been deposited with you hereunder,
together with any interest earned on the Fund in accordance with Section 2
hereof. You shall at the same time give notice to the Depositor of the aggregate
amounts of subscription funds and/or interest so returned.

                  4. The Parties further agree with you as follows:

                  (a) Your duties and responsibilities shall be limited solely
to those expressly set forth in this Agreement and are ministerial in nature.
You shall neither be subject to nor obliged to recognize any other agreement
between, or other direction or instruction of, any or all of the Parties or any
Subscriber even though reference thereto may be made herein; PROVIDED, HOWEVER,
that with your written consent, this Agreement may be amended at any time or
times by an instrument in writing signed by the Parties.

                  (b) You are authorized, in your sole discretion, to disregard
any and all notices or instructions given by any of the Parties or by any other
person, firm, or corporation, except only such notices or instructions as are
hereunder provided for and orders or process of any court entered or issued with
or without jurisdiction. If the Fund or any part thereof is at any time
attached, garnished, or levied upon under any court order or in case the
payment, assignment, transfer, conveyance, or delivery of the Fund shall be
stayed or enjoined by any court order, or in case any order, judgment, or decree
shall be made or entered by any court affecting the Fund or any part thereof,
then and in any such event you are authorized, in your sole discretion, to rely
upon and comply with any such order, writ, judgment, or decree that you are
advised by legal counsel of your own choosing is binding upon you, and if you
comply with any such order, writ, judgment, or decree you shall not be liable to
any of the Parties or to any other person, firm, or corporation by reason of
such compliance even though such order, writ, judgment, or decree may be
subsequently reversed, modified, annulled, set aside, or vacated.

                  (c) You shall be fully protected in relying upon any written
notice, demand, certificate, document, or instrument believed by you in good
faith to be genuine and to have been signed or presented by the proper person or
persons or Party or Parties. The Parties


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shall provide you with a list of officers and employees who shall be authorized
to deliver instructions hereunder. You shall not be liable for any action taken
or omitted by you in connection herewith in good faith and in the exercise of
your own best judgment.

                  (d) Should any dispute arise with respect to the delivery,
ownership, right of possession, and/or disposition of the subscription funds
deposited with you hereunder, or should any claim be made upon any such
subscription funds by a third party, you, upon receipt of written notice of such
dispute by any of the Parties or by a third party, are authorized and directed
to retain in your possession all or any of such subscription funds until such
dispute shall have been settled either by mutual agreement of the parties
involved or by final order, decree, or judgment of any court in the United
States.

                  (e) If for any reason funds are deposited in the escrow
account other than by transfer of immediately available funds, you shall proceed
as soon as practicable to collect checks, drafts, and other collection items at
any time deposited with you hereunder. All such collections shall be subject to
the usual collection agreement regarding items received by your commercial
banking department for deposit or collection; PROVIDED, HOWEVER, that if any
check, draft, or other collection item at any time deposited with you hereunder
is returned to you as being uncollectable (except by reason of an account
closing), you shall attempt a second time to collect such item before returning
such item to the Depositor as uncollectable. Subject to the foregoing, you shall
promptly notify the Parties of any uncollectable check, draft, or other
collection item deposited with you hereunder and shall promptly return such
uncollectable item to the Depositor, in which case you shall not be liable to
pay any interest on the subscription funds represented by such uncollectable
item. In no event, however, shall you be required or have a duty to take any
legal action to enforce payment of any check or note deposited hereunder.

                  (f) You shall not be responsible for the sufficiency or
accuracy of the form, execution, validity, or genuineness of documents now or
hereafter deposited with you hereunder, or for any lack of endorsement thereon
or for any description therein, nor shall you be responsible or liable in any
respect on account of the identity, authority, or rights of the persons
executing or delivering or purporting to execute or deliver any such document,
or endorsement or this Agreement. You shall not be liable for any loss sustained
as a result of any investment made pursuant to the instructions of the Parties
or as a result of any liquidation of an investment prior to its maturity or the
failure of the Parties to give you any instructions to invest or reinvest the
Fund or any earnings thereon.

                  (g) All notices required or desired to be delivered hereunder
shall be in writing and shall be effective when delivered personally on the day
delivered, or when given by registered or certified mail, postage prepaid,
return receipt requested, on the day of receipt, addressed as follows (or to
such other address as the party entitled to notice shall hereafter designate in
accordance with the terms hereof):

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                        if to a Partnership, the Partnerships or the General
                        Partner:

                        Demeter Management Corporation
                        Two World Trade Center, 62nd Floor
                        New York, New York 10048
                        Attn: Mr. Robert E. Murray
                              President

                        if to the Depositor:

                        Dean Witter Reynolds Inc.
                        Two World Trade Center, 62nd Floor
                        New York, New York 10048
                        Attn: Mr. Robert E. Murray
                              Senior Vice-President

                        in either case with a copy to:

                        Cadwalader, Wickersham & Taft
                        100 Maiden Lane
                        New York, New York 10038
                        Attn: Edwin L. Lyon, Esq.

                        if to you:

                        The Chase Manhattan Bank
                        450 W. 33rd Street, 15th Floor
                        New York, New York 10001
                        Attn: Mr. Paul Gilkeson

Whenever, under the terms hereof, the time for giving a notice or performing an
act falls on a Saturday, Sunday, or legal holiday, such time shall be extended
to the next business day.

                  (h) The Depositor agrees to indemnify, defend, and hold you
harmless from and against, any and all loss, damage, tax, liability, and expense
that may be incurred by you arising out of or in connection with your duties
hereunder, except as caused by your gross negligence, bad faith, or willful
misconduct, including the legal costs and expenses of defending yourself against
any claim or liability in connection with your performance hereunder.

                  (i) You shall be paid by the Depositor for your services a fee
of $3,000 in advance for each twelve month period; the first twelve month period
beginning from the date of this Agreement (each twelve month period shall be
called a "Fee Period").

                  (j) It is understood that you may at any time resign hereunder
as Escrow Agent by giving written notice of your resignation to the Parties at
their address set forth above at least 20 days prior to the date specified for
such resignation to take effect, and upon the effective date of such
resignation, all property then held by you hereunder shall be delivered by you
to such person as may be designated jointly by the Parties in writing, whereupon
all your


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obligations hereunder shall cease and terminate. If you shall resign prior to
the conclusion of any Fee Period you shall pay to the Depositor an amount equal
to the product of $3,000 and a fraction, the numerator of which shall be the
number of days remaining in the Fee Period and the denominator of which shall be
365. If no successor Escrow Agent has been appointed or has accepted such
appointment by such date, all your obligations hereunder shall nevertheless
cease and terminate. Your sole responsibility thereafter shall be to keep safely
all property then held by you and to deliver the same to a person designated by
the Parties hereto or in accordance with the directions of a final order or
judgment of a court of competent jurisdiction.

                  5. This Agreement shall be governed by and construed in
accordance with the law of the State of New York and any action brought
hereunder shall be brought in the courts of the State of New York, sitting in
the County of New York.

                  6. The undersigned Escrow Agent hereby acknowledges and agrees
to hold, deal with, and dispose of, the Fund (including any interest earned
thereon) and any other property at any time held by the Escrow Agent hereunder
in accordance with this Agreement.



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            If the foregoing Agreement is satisfactory to you, please so
indicate by signing at the place provided below.

                          Sincerely,

                          MORGAN STANLEY DEAN WITTER SPECTRUM SELECT L.P.


                          By: Demeter Management Corporation, as general partner


                          By: /s/ Robert E. Murray
                              ------------------------------------------
                              Robert E. Murray
                              President


                          MORGAN STANLEY DEAN WITTER SPECTRUM TECHNICAL L.P.


                          By: Demeter Management Corporation, as general partner


                          By: /s/ Robert E. Murray
                              ------------------------------------
                              Robert E. Murray
                              President


                          MORGAN STANLEY DEAN WITTER SPECTRUM STRATEGIC L.P.


                          By: Demeter Management Corporation, as general partner


                          By: /s/ Robert E. Murray
                              ------------------------------------
                              Robert E. Murray
                              President

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                          MORGAN STANLEY DEAN WITTER SPECTRUM GLOBAL BALANCED
                             L.P.


                          By: Demeter Management Corporation, as general partner


                          By: /s/ Robert E. Murray
                              ------------------------------------
                              Robert E. Murray
                              President


                          MORGAN STANLEY DEAN WITTER SPECTRUM CURRENCY L.P.


                          By: Demeter Management Corporation, as general partner


                          By: /s/ Robert E. Murray
                              ------------------------------------
                              Robert E. Murray
                              President

                          MORGAN STANLEY DEAN WITTER SPECTRUM COMMODITY L.P.

                          By: Demeter Management Corporation, as general partner


                          By: /s/ Robert E. Murray
                              ------------------------------------
                              Robert E. Murray
                              President


                          DEAN WITTER REYNOLDS INC.


                          By: /s/ Robert E. Murray
                              ------------------------------------
                              Robert E. Murray
                              Senior Vice-President

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                          Accepted and agreed to:


                          THE CHASE MANHATTAN BANK


                          By: /s/ Paul J. Gilkeson
                              ------------------------------------
                              P.J. Gilkeson
                              Vice-President









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