SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
                                   ----------
                                    FORM 10-K

                        FOR ANNUAL AND TRANSITION REPORTS
                     PURSUANT TO SECTIONS 13 OR 15(d) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


(Mark One)
[X]      ANNUAL REPORT PURSUANT TO SECTION 13 or 15(d) OF THE SECURITIES
         EXCHANGE ACT OF 1934

For the fiscal year ended December 31, 2004
                          -----------------

                                                                  OR

[ ]      TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
         EXCHANGE  ACT OF 1934

For the transition period from __________ to __________

                  Commission File Numbers 001-16443, 333-64879
                                          --------------------


                            MS STRUCTURED ASSET CORP.
                                  On behalf of
                            SATURNS Trust No. 2001-4
             (Exact name of registrant as specified in its charter)


          Delaware                                       13-4026700
-------------------------------                ---------------------------------
(State or other jurisdiction of                (IRS Employer Identification No.)
 incorporation or organization)


        1585 Broadway, Second Floor
            New York, New York
          Attention: Madhu Philips                        10036
    --------------------------------------              ----------
   (Address of principal executive office)              (Zip Code)

       Registrant's telephone number, including area code: (212) 761-2520

           Securities registered pursuant to Section 12(b) of the Act:

   Title of Each Class                 Name of Each Exchange on Which Registered
------------------------------         -----------------------------------------
SATURNS Cummins Engine Company                    New York Stock Exchange
Debenture-Backed Series 2001-4
Callable Units

          Securities registered pursuant to Section 12(g) of the Act:

                                      None


<PAGE>


     Indicate  by check  mark  whether  registrant  (1) has  filed  all  reports
required to be filed by Section 13 or 15(d) of the  Securities  Exchange  Act of
1934  during  the  preceding  12 months  (or for such  shorter  period  that the
registrant was required to file such reports),  and (2) has been subject to such
filing requirements for the past 90 days. Yes X  No
                                             ---   ---

     Indicate by check mark if disclosure of delinquent  filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of registrant's  knowledge,  in definitive proxy or information  statements
incorporated by reference in Part III of this Form 10-K or any amendment to this
Form 10-K. [ ]

     All of the common stock of the registrant is held by Morgan Stanley.

     Indicate by check mark whether the  registrant  has filed all documents and
reports  required  to be  filed by  Section  12,  13 or 15(d) of the  Securities
Exchange Act of 1934 subsequent to the  distribution of securities  under a plan
confirmed by a court. Yes ___ No ___

                      As of February 20, 2005, 1,000 shares of common stock, par
value $1.00 per share, were outstanding.


                      DOCUMENTS INCORPORATED BY REFERENCE:

        The distribution reports to security holders filed on Form 8-K during
the Fiscal Year in lieu of reports on Form 10-Q.


                                Introductory Note

The Registrant is the depositor under the trust agreements for it various
SATURNS Units listed on the New York Stock Exchange. The Units do not represent
obligations of or interests in the Depositor. Pursuant to staff administrative
positions established in various no-action letters, see e.g. Corporate Asset
Backed Corporation (available August 9, 1995), the Registrant is not required to
respond to various items of Form 10-K. Such items are designated herein as "Not
applicable." Distribution reports detailing receipts and distributions by each
trust are filed shortly after each distribution date on Form 8-K in lieu of
reports on Form 10-Q.

The underlying security issuer or guarantor, as applicable, of the securities
held by each of the trusts is subject to the informational requirements of the
Exchange Act. The underlying security issuer or guarantor, as applicable,
currently files reports, proxy statements and other information with the SEC.
For information regarding such underlying security issuer or guarantor, you
should refer to such reports. These periodic, current and other reports and
other information can be inspected and copied at the public reference facilities
maintained by the SEC at Room 1024, 450 Fifth Street, N.W., Washington, D.C.
20549. Copies of those materials can be obtained by making a written request to
the SEC, Public Reference Section, 450 Fifth Street, N.W., Washington, D.C.
20549, at prescribed rates. The SEC also maintains a website on the internet at
http://www.sec.gov at which users can view and download copies of reports,
proxy, information statements and other information filed electronically. In
addition, those reports and other information may also be obtained from the
underlying security issuer by making a request to the underlying security
issuer. The trust, the trustee, the Registrant, and their affiliates have not
verified, have not undertaken to verify, and will not verify, the content of any
such reports or information. The name and the central index key (CIK) for each
underlying security issuer or guarantor is set forth below:

Trust            Underlying Security Issuer or Guarantor                 CIK
2001-4                       Cummins Inc.                             0000026712


<PAGE>


                                     PART I

ITEM 1.  BUSINESS

         Not Applicable

ITEM 2.  PROPERTIES

         Not Applicable

ITEM 3.  LEGAL PROCEEDINGS

         None

ITEM 4.  SUBMISSION OF MATTERS TO A VOTE OF SECURITY HOLDERS

         None


                                     PART II

ITEM 5.  MARKET FOR REGISTRANT'S COMMON EQUITY AND RELATED STOCKHOLDER MATTERS

The Units issued by the SATURNS trusts listed below representing investors'
interest in such trust are represented by one or more physical certificates
registered in the name of Cede & Co., the nominee of The Depository Trust
Company. These Units are listed on the New York Stock Exchange:

SATURNS Trust No. 2001-4 (Cummins Engine Company Debenture-Backed)

ITEM 6.  SELECTED FINANCIAL DATA

         Not Applicable

ITEM 7.  MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS
         OF OPERATIONS

         Not Applicable

ITEM 7A. QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

         Not Applicable

ITEM 8.  FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

         Not Applicable


<PAGE>


ITEM 9.  CHANGES IN AND DISAGREEMENTS WITH ACCOUNTANTS ON ACCOUNTING AND
         FINANCIAL DISCLOSURE

         None

ITEM 9A. CONTROLS AND PROCEDURES

         Not Applicable


                                    PART III

ITEM 10. DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

         Not Applicable

ITEM 11. EXECUTIVE COMPENSATION

         Not Applicable


ITEM 12. SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

         None

ITEM 13. CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

         None

ITEM 14. PRINCIPAL ACCOUNTING FEES AND SERVICES

         Not Applicable

                                     PART IV

ITEM 15. EXHIBITS, FINANCIAL STATEMENT SCHEDULES, AND REPORTS ON FORM 8-K

         (a) The following documents are filed as part of this Report: None

         (b) Reports on Form 8-K:

See Table Below:


<PAGE>

<TABLE>
<CAPTION>
---------------------- --------------------- ------------------------------ ------------------------------------------
<S>                    <C>                   <C>                            <C>
 SATURNS Trust No.:        Closing Date              Payment Dates              Form 8-K Filing Dates (Not Trust
                                                                              Agreement Filings in connection with
                                                                                          Closing Date)

                                                                                           For FY 2004

---------------------- --------------------- ------------------------------ ------------------------------------------

---------------------- --------------------- ------------------------------ ------------------------------------------
2001-4                 6/4/01                March 1 and September 1        March 8, 2004 and September 7, 2004
---------------------- --------------------- ------------------------------ ------------------------------------------
</TABLE>

         (c) Exhibits:

Exhibit 31.1      Rule 13a-14(d) Certification
Exhibit 31.2      Trustee Compliance Certification

The trust covered by this annual report was formed prior to June 30, 2003 and
there is no requirement in the trust agreement for the preparation of a report
by an independent public accountant regarding the trustee's compliance with its
obligations.

         (d) Not applicable


<PAGE>


                                   SIGNATURES

     Pursuant  to the  requirements  of  Section  13 or 15(d) of the  Securities
Exchange Act of 1934, the Registrant has duly caused this report to be signed on
its behalf by the undersigned, thereunto duly authorized.



     Date: March 30, 2005

                                             MS STRUCTURED ASSET CORP.
                                             (Registrant)



                                             By:     /s/ Madhu Philips
                                                --------------------------
                                             Name:   Madhu Philips
                                             Title:  Vice President


<PAGE>


                                                                    Exhibit 31.1
                                  CERTIFICATION

I, Madhu Philips, certify that:

1. I have reviewed this annual report on Form 10-K, and all reports on Form 8-K
containing distribution or servicing reports filed in respect of periods
included in the year covered by this annual report, of MS Structured Asset Corp.
on behalf of SATURNS Trust No. 2001-4;

2. Based on my knowledge, the information in these reports, taken as a whole,
does not contain any untrue statement of a material fact or omit to state a
material fact necessary to make the statements made, in light of the
circumstances under which such statements were made, not misleading as of the
last day of the period covered by this annual report;

3. Based on my knowledge, the distribution or servicing information required to
be provided to the depositor by the trustee under the pooling and servicing, or
similar, agreement, for inclusion in these reports is included in these reports;
and

4. I am responsible for reviewing the activities performed by the depositor and
the trustee under the pooling and servicing, or similar, agreement and based
upon my knowledge and the annual compliance review required under that
agreement, and except as disclosed in the reports, the depositor and trustee
have each fulfilled its obligations under that agreement.

In giving the certifications above, I have reasonably relied on information
provided to me by the following unaffiliated parties: LaSalle Bank National
Association and its officers and agents.



                                              By:    /s/ Madhu Philips
                                                 -----------------------
                                              Name:  Madhu Philips
                                              Title: Vice President
                                              Date:  March 30, 2005


<PAGE>


                                                                    Exhibit 31.2
                              COMPLIANCE STATEMENT

     In  connection  with the  preparation  and delivery of the annual report on
Form 10-K of MS Structured Asset Corp. on behalf of SATURNS Trust No. 2001-4 for
the fiscal year ending December 31, 2004, and the certifications  given by Madhu
Philips with respect thereto, the undersigned hereby certifies that he is a duly
elected  Vice  President  of  LaSalle  Bank  National  Association  and  further
certifies in his capacity as such as follows:


1. LaSalle Bank National Association has prepared all distribution reports with
respect to each distribution date for SATURNS Trust No. 2001-4, and has filed a
copy of such reports on Form 8-K during the fiscal year as described on Exhibit
A hereto.

2. I have reviewed all reports on Form 8-K containing distribution reports filed
in respect of periods included in the fiscal year covered by the annual report
of MS Structured Asset Corp. on behalf of SATURNS Trust No. 2001-4;

3. I am familiar with the operations of LaSalle Bank National Association with
respect to the SATURNS program and SATURNS Trust No. 2001-4 and the requirement
imposed by the applicable trust agreement;

4. Based on my knowledge, the information in the distribution reports, taken as
a whole, does not contain any untrue statement of a material fact or omit to
state a material fact necessary to make the statements made, in light of the
circumstances under which such statements were made, not misleading as of the
last day of the period covered by the annual report;

5. Based on my knowledge, the information required to be provided under each
trust agreement, for inclusion in these reports, is included in these reports;

6. Based on my knowledge, and except as disclosed in the reports, the trustee
has fulfilled its obligations, including any servicing obligations, under the
trust agreement.

7. Based on my knowledge, and except as disclosed in the reports, there are no
material legal proceedings with respect to any trust, involving the trust or
LaSalle Bank National Association as trustee.


                                              By:    /s/ Cynthia Reis
                                                 --------------------------
                                              Name:  Cynthia Reis
                                              Title: Senior Vice President
                                              Date:  March 16, 2005


<PAGE>


                                                                       EXHIBIT A
<TABLE>
<CAPTION>
---------------------- --------------------- ------------------------------ ------------------------------------------
<S>                    <C>                   <C>                            <C>
 SATURNS Trust No.:        Closing Date              Payment Dates              Form 8-K Filing Dates (Not Trust
                                                                              Agreement Filings in connection with
                                                                                          Closing Date)

                                                                                           For FY 2004

---------------------- --------------------- ------------------------------ ------------------------------------------

---------------------- --------------------- ------------------------------ ------------------------------------------
2001-4                 6/4/01                March 1 and September 1        March 8, 2004 and September 7, 2004
---------------------- --------------------- ------------------------------ ------------------------------------------
</TABLE>