ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

Exhibit 99.15(a)


EXECUTION COPY


ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT

THIS ASSIGNMENT, ASSUMPTION AND RECOGNITION AGREEMENT (this
"Assignment"), dated as of March 1, 2006, is entered into among Morgan Stanley
Capital I Inc., a Delaware corporation (the "Depositor"), Morgan Stanley
Mortgage Capital Inc. ("MSMCI"), Wachovia Mortgage Corporation as seller
("Wachovia," or the "Seller"), and acknowledged by LaSalle Bank National
Association, as trustee (the "Trustee") of Morgan Stanley Mortgage Loan Trust
2006-5AR (the "Trust").

RECITALS

WHEREAS MSMCI and the Seller have entered into a certain Seller's
Purchase, Warranties and Interim Servicing Agreement, dated as of February 28,
2005 (as amended or modified to the date hereof, the "Agreement"), pursuant to
which MSMCI has acquired certain Mortgage Loans pursuant to the terms of the
Agreement;

WHEREAS the Depositor has agreed, on the terms and conditions contained
herein, to purchase from MSMCI certain of the Mortgage Loans (the "Specified
Mortgage Loans") which are subject to the provisions of the Agreement and are
listed on the mortgage loan schedule attached as Exhibit I hereto (the
"Specified Mortgage Loan Schedule"); and

WHEREAS the Trustee, on behalf of the Trust, has agreed, on the terms
and conditions contained herein, to purchase from the Depositor the Specified
Mortgage Loans;

NOW, THEREFORE, in consideration of the mutual promises contained herein
and other good and valuable consideration (the receipt and sufficiency of
which are hereby acknowledged), the parties agree as follows:

1. Assignment and Assumption

(a) On and as of the date hereof, MSMCI hereby sells, assigns and
transfers to the Depositor all of its right, title and interest in the
Specified Mortgage Loans and all rights and obligations related thereto as
provided under the Agreement to the extent relating to the Specified Mortgage
Loans, the Depositor hereby accepts such assignment from MSMCI (the "First
Assignment and Assumption"), and the Seller hereby acknowledges the First
Assignment and Assumption.

MSMCI specifically reserves and does not assign to the
Depositor hereunder any and all right, title and interest in, to and under and
all obligations of MSMCI with respect to any Mortgage Loans subject to the
Agreement which are not the Specified Mortgage Loans.

(b) On and as of the date hereof, immediately after giving effect to the
First Assignment and Assumption, the Depositor hereby sells, assigns and
transfers to the Trustee, on behalf of the Trust, all of its right, title and
interest in the Specified Mortgage Loans and all rights and obligations
related thereto as provided under the Agreement to the extent relating to the
Specified Mortgage Loans, and the Trustee, on behalf of the Trust, hereby
accepts such assignment from the Depositor (the "Second Assignment and
Assumption"), and the Seller hereby acknowledges the Second Assignment and
Assumption.

(c) On and as of the date hereof, MSMCI represents and warrants to the
Depositor and the Trustee that MSMCI has not taken any action that would serve
to impair or encumber the respective


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ownership interests of the Depositor and the Trustee in the Specified Mortgage
Loans since the date of MSMCI's acquisition of the Specified Mortgage Loans.

2. Recognition of Trustee

(a) From and after the date hereof, both MSMCI and the Seller shall note
the transfer of the Specified Mortgage Loans to the Trustee, in their
respective books and records and shall recognize the Trustee, on behalf of the
Trust, as of the date hereof, as the owner of the Specified Mortgage Loans. It
is the intention of the Seller, the Servicer, the Depositor, the Trustee and
MSMCI that this Assignment shall be binding upon and inure to the benefit of
the Depositor, the Trustee and MSMCI and their respective successors and
assigns.

(b) Without in any way limiting the foregoing, the parties confirm that
this Assignment includes the rights relating to amendments or waivers under
the Agreement. Accordingly, the right of MSMCI to consent to any amendment of
the Agreement and its rights concerning waivers as set forth in Sections 11.02
and 8.02 of the Agreement shall be exercisable, to the extent any such
amendment or waiver affects the Specified Mortgage Loans or any of the rights
under the Agreement with respect thereto (other than the servicing of the
Specified Mortgage Loans, which shall be enforced by the Master Servicer) by
the Trustee as assignee of MSMCI.

(c) It is expressly understood and agreed by the parties hereto that (i)
this Assignment is executed and delivered by LaSalle Bank National
Association, not individually or personally but solely on behalf of the Trust,
as the assignee, in the exercise