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

       |X|        ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                  SECURITIES EXCHANGE ACT OF 1934 FOR THE FISCAL YEAR ENDED
                  DECEMBER 31, 2006

                                      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 Number of issuing entity: 1-32867

                   STRATS(SM) TRUST FOR ALLSTATE CORPORATION
                          SECURITIES, SERIES 2006-3
          (Exact name of issuing entity as specified in its charter)

                    SYNTHETIC FIXED-INCOME SECURITIES, INC.
       (Exact name of depositor and sponsor as specified in its charter)

              New York
    (State of incorporation or                        52-2316399
organization of the issuing entity)        (IRS Employer Identification No.)

      One Wachovia Center
     301 S. College Street
   Charlotte, North Carolina
     (Address of principal           28288            (704) 374-6611
      executive offices)          (Zip Code)        (Telephone Number)


                        SECURITIES REGISTERED PURSUANT
                         TO SECTION 12(b) OF THE ACT:

Title of Class                                  Name of Registered Exchange
--------------                                  ---------------------------
STRATS (SM) Certificates, Series 2006-3      New York Stock Exchange ("NYSE")

                        SECURITIES REGISTERED PURSUANT
                       TO SECTION 12(g) OF THE ACT: NONE

      Indicate by check mark if the registrant is a well-known seasoned
issuer, as defined in Rule 405 of the Securities Act.
                                                                |_| Yes |X| No

      Indicate by check mark if the registrant is not required to file reports
pursuant to Section 13 or Section 15(d) of the Act.
                                                                |_| Yes |X| No


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      Indicate by check mark whether the 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.
                                                                |X| Yes |_| No

      Indicate by check mark if disclosure of delinquent filers pursuant to
Item 405 of Regulation S-K (ss. 229.405 of this chapter) 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.               |X|

      Indicate by check mark whether the registrant is a large accelerated
filer, an accelerated filer, or a non-accelerated filer. See definition of
"accelerated filer and large accelerated filer" in Rule 12b-2 of the Exchange
Act. (Check one):

Large accelerated filer |_|  Accelerated filer |_|  Non-accelerated filer |X|

      Indicate by check mark whether the registrant is a shell company (as
defined in Rule 12b-2 of the Exchange Act).
                                                                |_| Yes |X| No

      State the aggregate market value of the voting and non-voting common
equity held by non-affiliates computed by reference to the price at which the
common equity was last sold, or the average bid and asked price of such common
equity, as of the last business day of the registrant's most recently
completed second fiscal quarter.

      Not applicable.

                      DOCUMENTS INCORPORATED BY REFERENCE

      List hereunder the following documents if incorporated by reference and
the part of the Form 10-K (e.g., Part I, Part II, etc.) into which the
document is incorporated: (1) Any annual report to security holders; (2) Any
proxy information statement; and, (3) Any prospectus filed pursuant to Rule
424(b) or (c) under the Securities Act of 1933. The listed documents should be
clearly described for identification purposes (e.g., annual report to security
holders for fiscal year ended December 24, 1980).

      None.


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                                    PART I

The following Items have been omitted in accordance with General Instruction J
to Form 10-K:

      Item 1. Business.

      Item IA. Risk Factors.

      Item 2. Properties.

      Item 3. Legal Proceedings.

      Item 4. Submission of Matters to a Vote of Security Holders.

Item 1B. Unresolved Staff Comments

      None.

                                    PART II

The following Items have been omitted in accordance with General Instruction J
to Form 10-K:

      Item 5. Market for Registrant's Common Equity, Related Stockholder
      Matters and Issuer Purchases of Equity Securities.

      Item 6. Selected Financial Data.

      Item 7. Management's Discussion and Analysis of Financial Condition and
      Results of Operations.

      Item 7A. Quantitative and Qualitative Disclosures About Market Risk.

      Item 8. Financial Statements and Supplementary Data.

      Item 9. Changes in and Disagreement with Accountants on Accounting and
      Financial Disclosure.

      Item 9A. Controls and Procedures.

Item 9B.  Other Information.

      None.

                                   PART III

The following Items have been omitted in accordance with General Instruction J
to Form 10-K:

      Item 10. Directors and Executive Officers of the Registrant.

      Item 11. Executive Compensation.

      Item 12. Security Ownership of Certain Beneficial Owners and Management
      and Related Stockholder Matters.


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      Item 13. Certain Relationships and Related Transactions.

      Item 14. Principal Accountant Fees and Services.

Substitute information provided in accordance with General Instruction J to
Form 10-K:

Item 1112(b) of Regulation AB. Significant Obligors of Pool Assets (Financial
Information).

      The Allstate Corporation, the issuer of the underlying securities, is
subject to the information reporting requirements of the Securities Exchange
Act of 1934 (the "Exchange Act"). For information on The Allstate Corporation
please see its periodic and current reports filed with the Securities and
Exchange Commission (the "Commission") under its Exchange Act file number,
001-11840. The Commission maintains a site on the World Wide Web at
"http://www.sec.gov" at which users can view and download copies of reports,
proxy and information statements and other information filed electronically
through the Electronic Data Gathering, Analysis and Retrieval system, or
"EDGAR." Periodic and current reports and other information required to be
filed pursuant to the Exchange Act by The Allstate Corporation may be accessed
on this site. Neither Synthetic Fixed-Income Securities, Inc. nor the Trustee
has participated in the preparation of such reporting documents, or made any
due diligence investigation with respect to the information provided therein.
Neither Synthetic Fixed-Income Securities, Inc. nor the Trustee has verified
the accuracy or completeness of such documents or reports. There can be no
assurance that events affecting the issuer of the underlying securities or the
underlying securities themselves have not occurred or have not yet been
publicly disclosed which would affect the accuracy or completeness of the
publicly available documents described above.

Item 1114(b)(2) of Regulation AB. Credit Enhancement and Other Support, Except
for Certain Derivatives Instruments (Financial Information).

      None.

Item 1115(b) of Regulation AB. Certain Derivatives Instruments (Financial
Information).

      None.

Item 1117 of Regulation AB. Legal Proceedings.

      There are no legal proceedings pending, or any proceedings known to be
contemplated, by governmental authorities against the depositor, the Trustee
or the issuing entity, or any property thereof, that is material to the
holders of the Certificates.

Item 1119 of Regulation AB. Affiliations and Certain Relationships and Related
Transactions.

      Omitted in accordance with the Instruction to Item 1119. See the
information in the prospectus for the issuing entity filed under Rule 424(b)
of the Securities Act of 1933.

Item 1122 of Regulation AB. Compliance with Applicable Servicing Criteria.

      The Trustee has been identified as a party participating in the
servicing function during the reporting period with respect to the pool assets
held by the issuing entity. The Trustee's report on an assessment of
compliance with the servicing criteria applicable to it during the Issuing
Entity's fiscal year ending December 31, 2006 and an attestation report by a
registered independent public accounting firm regarding the Trustee's related
report on assessment are attached as exhibits to this Form 10-K. Neither


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the report on assessment or the related attestation report has identified any
material instances of noncompliance with the servicing criteria described in
the report on assessment as being applicable to the Trustee.

Item 1123 of Regulation AB. Servicer Compliance Statement.

      The Trustee has provided a compliance statement, signed by an authorized
officer, attached as an exhibit to this Form 10-K.

                                    PART IV

Item 15.  Exhibits, Financial Statement Schedules.

      (a)   List of Documents Filed as Part of this Report

            (1)   Not Applicable.

            (2)   Not Applicable.

            (3)   See Item 15 (b), below.

      (b)   Exhibits Required by Item 601 of Regulation S-K.

4.1   Series Supplement, dated as of April 28, 2006 (incorporated by reference
      to Exhibit 4.1 of the Issuing Entity's Current Report on Form 8-K filed
      on May 12, 2006).

31.1  Rule 13a-18/15d-18 Certification (Section 302 Certification).

33.1  Report on Assessment of Compliance with Applicable Servicing Criteria of
      The Bank of New York for the year ended December 31, 2006.

34.1  Independent Accountants' Attestation Report concerning servicing
      activities of The Bank of New York for the year ended December 31, 2006.

35.1  Compliance Statement of The Bank of New York for the year ended December
      31, 2006.

      (c)   Omitted.


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                                  SIGNATURES

      Pursuant to the requirements of Section 13 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.

                                   Synthetic Fixed-Income Securities, Inc.
                                   (Depositor)


Dated: March 29, 2007              By:  /s/ James Whang
                                        --------------------------------------
                                        James Whang
                                        Director
                                        (senior officer of depositor in charge
                                        of securitization)


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                                 EXHIBIT INDEX

EXHIBIT        DESCRIPTION

4.1            Series Supplement, dated April 28, 2006 (incorporated
               by reference to Exhibit 4.1 to the Issuing Entity's
               Current Report on Form 8-K filed on May 12, 2006).

31.1           Rule 13a-18/15d-18 Certification (Section 302
               Certification).

33.1           Report on Assessment of Compliance with Applicable
               Servicing Criteria of The Bank of New York for the year
               ended December 31, 2006.

34.1           Independent Accountants' Attestation Report concerning
               servicing activities of The Bank of New York for the
               year ended December 31, 2006.

35.1           Servicer Compliance Statement of The Bank of New York
               for the year ended December 31, 2006.


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