EXHIBIT 8.1



                      [DAVIS POLK & WARDWELL LETTERHEAD]



                                                     September 25, 2003


Re:  CBT Series 2003-1 Units Trust

MS Structured Asset Corp.
1585 Broadway
New York, New York  10036

Ladies and Gentlemen:

     We have acted as special tax counsel to MS Structured Asset Corp. (the
"Depositor") and Morgan Stanley & Co. Incorporated (the "Underwriter"),
(together, "Morgan Stanley") in connection with the offering of $25,000,000
principal amount of Corporate Bond TRACERS(SM) Units (the "Units"), each Unit
representing an undivided interest in the CBT Series 2003-1 Units Trust (the
"Trust"), pursuant to the Prospectus dated March 5, 2003 (the "Prospectus") and
the Supplement thereto dated September 9, 2003 (the "Prospectus Supplement").
The Units are to be issued by the Trust pursuant to the Trust Agreement dated
as of September 25, 2003 (the "Trust Agreement") between LaSalle Bank National
Association, as trustee (the "Trustee"), and Depositor. All capitalized terms
used herein and not otherwise defined shall have the respective meanings set
forth in the Trust Agreement.

     We have examined originals or copies, certified or otherwise identified to
our satisfaction, of such documents, certificates and other instruments as we
have deemed necessary for the purposes of this opinion. Moreover, we have
assumed that the Trustee will conduct the affairs of the Trust in accordance
with the terms of the Trust Agreement.

     On the basis of the foregoing, we are of the opinion that under United
States federal income tax law, the Trust will not be classified as an
association taxable as a corporation and will be classified as a grantor trust
under the Internal Revenue Code of 1986, as amended, and as such will not be
subject to United States federal income tax.



MS Structured Asset Corp.              2                     September 25, 2003


     Furthermore, we are of the opinion that the statements contained in the
Prospectus Supplement under the caption "United States Federal Income
Taxation," to the extent that they constitute matters of United States federal
income tax law or legal conclusions with respect thereto, are a fair and
accurate summary of the matters addressed therein.

     We hereby consent to the use of our name under the caption "United States
Federal Income Taxation" in the Prospectus Supplement. The issuance of such a
consent does not concede that we are an "Expert" for the purposes of the
Securities Act of 1933.

     We are members of the Bar of the State of New York and our opinion is
limited to the laws of the State of New York and the Federal laws of the United
States.

                                           Very truly yours,


                                           /s/ Davis Polk & Wardwell