UNITED STATES
                      SECURITIES AND EXCHANGE COMMISSION
                            WASHINGTON, D.C. 20549

                                    ------

                                   FORM 10-K

(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, 2002
                                   -----------------

                                      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: 333-74674-04
                                             ------------

                  CWMBS, Inc., Alternative Loan Trust 2002-4
               Mortgage Pass-Through Certificates, Series 2002-6
               -------------------------------------------------
            (Exact name of Registrant as specified in its charter)


          Delaware                                      95-4449516
-------------------------------           ------------------------------------
(State or other jurisdiction of           (IRS Employer Identification Number)
incorporation or organization)

c/o  Countrywide Home Loans Servicing LP
     4500 Park Granada
     Calabasas, California                                 91302
----------------------------------------  ------------------------------------
(Address of principal executive offices)                 (Zip Code)

Registrant's telephone number, including area code:   (818) 225-3000
                                                      --------------

Securities registered pursuant to Section 12(b) of the Act:  None
                                                             ----

Securities registered pursuant to Section 12(g) of the Act:  None
                                                             ----


<PAGE>


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. Yes  X   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. [ ]

Indicate by check mark whether the registrant is an accelerated filer (as
defined in Rule 12b-2 of the Act. Yes      No X
                                      ---    ---

State the aggregate market value of the voting and non-voting common equity
held by non-affiliates of the Registrant: Not applicable
                                          --------------

Indicate the number of shares outstanding of each of the registrant's classes
of common stock, as of December 31, 2002: Not applicable
                                          --------------


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<PAGE>


DOCUMENTS INCORPORATED BY REFERENCE

                                     None.

                                 *     *     *


     This Annual Report on Form 10-K (the "Report") is filed with respect to
the trust fund entitled Alternative Loan Trust 2002-4 (the "Trust Fund")
formed pursuant to the pooling and servicing agreement dated as of March 1,
2002 (the "Pooling and Servicing Agreement") among CWMBS, Inc., as depositor
(the "Company"), Countrywide Home Loans Servicing LP, as seller and master
servicer (the "Master Servicer"), and The Bank of New York, as trustee (the
"Trustee"), for the issuance of CWMBS, Inc., Mortgage Pass-Through
Certificates, Series 2002-6 (the "Certificates"). Certain information
otherwise required to be included in this Report by the Instructions to Form
10-K has been omitted in reliance on the relief granted to the Company in
CWMBS, Inc. (February 3, 1994) (the "Relief Letter").


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<PAGE>


                                    PART I


ITEM 1.   BUSINESS

          Not applicable. See the Relief Letter.

ITEM 2.   PROPERTIES

          Not applicable.  See the Relief Letter.

ITEM 3.   LEGAL PROCEEDINGS

          There were no material pending legal proceedings relating to the
          Trust Fund to which any of the Trust Fund, the Trustee, the Master
          Servicer or the Company was a party or of which any of their
          respective properties was the subject during the fiscal year covered
          by this Report, nor is the Company aware of any such proceedings
          contemplated by governmental authorities.

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

          No matter was submitted to a vote of Certificateholders, and no
          Certificateholder consent was solicited during the fiscal year
          covered by this Report.


                                      4
<PAGE>


                                    PART II


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

          (a)  Market Information. There is no established public trading
               market for the Certificates.

          (b)  Holders. As of December 31, 2002 there were less than 300
               holders of record of the Certificates.

          (c)  Dividends. Not applicable. See the Relief Letter. (Information
               as to distributions to Certificateholders is provided in the
               Registrant's monthly filings on Form 8-K.)

          (d)  Securities Authorized for Issuance Under Equity Compensation
               Plans. Not applicable.

          (e)  Item 701 of Regulation S-K. Not applicable. See the Relief
               Letter.

          (f)  Rule 463 of the Securities Act of 1933. Not applicable. See the
               Relief Letter.

ITEM 6.   SELECTED FINANCIAL DATA

          Not applicable. See the Relief Letter.

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

          Not applicable. See the Relief Letter.

ITEM 7A   QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK

          Not applicable.

ITEM 8.   FINANCIAL STATEMENTS AND SUPPLEMENTARY DATA

          Not applicable.  See the Relief Letter.

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

          None.


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<PAGE>


                                   PART III


ITEM 10.  DIRECTORS AND EXECUTIVE OFFICERS OF THE REGISTRANT

          Not applicable.  See the Relief Letter.

ITEM 11.  EXECUTIVE COMPENSATION

          Not applicable.  See the Relief Letter.

ITEM 12.  SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

          Information required by Item 201(d) of Regulation S-K: Not
          applicable.

          Information required by Item 403 of Regulation S-K:

          (a) Not applicable. See the Relief Letter.

          (b) Not applicable. See the Relief Letter.

          (c) Not applicable. See the Relief Letter.

ITEM 13.  CERTAIN RELATIONSHIPS AND RELATED TRANSACTIONS

          Not applicable.  See the Relief Letter.

ITEM 14.  CONTROLS AND PROCEDURES

          Not applicable. The Registrant is an Asset-Backed Issuer (as defined
          in Exchange Act Rules 13a-14(g) and 15d-14(g)) and is therefore not
          required to disclose information under Item 307 of Regulation S-K.
          See paragraph (c) of Item 307 of Regulation S-K.


                                      6
<PAGE>


                                    PART IV


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

          (a)    (1)  Pursuant to the Pooling and Servicing Agreement, the
                      Master Servicer is required (i) to deliver an annual
                      statement as to compliance with the provisions of the
                      Pooling and Servicing Agreement and certain other
                      matters (the "Annual Statement of the Master Servicer")
                      and (ii) to cause a firm of independent public
                      accountants to deliver an annual report as to
                      compliance with the servicing provisions of the Pooling
                      and Servicing Agreement (the "Annual Report of the Firm
                      of Accountants"). The Annual Statement of the Master
                      Servicer is attached as Exhibit 99.1 to this Report.
                      The Annual Report of the Firm of Accountants is
                      attached as Exhibit 99.2 to this Report. See Relief
                      Letter.

                 (2)  Not applicable.

                 (3)  The required exhibits are as follows:

                      o   Exhibit 3(i): Copy of Company's Certificate of
                          Incorporation (Filed as an Exhibit to Registration
                          Statement on Form S-3 (File No. 33-63714)).

                      o   Exhibit 3(ii): Copy of Company's By-laws (Filed as
                          an Exhibit to Registration Statement on Form S-3
                          (File No. 33-63714)).

                      o   Exhibit 4: Pooling and Servicing Agreement (Filed as
                          part of the Registrant's Current Report on Form 8-K
                          filed on May 3, 2002).

                      o   Exhibit 99.1:  Annual Statement of the Master
                          Servicer.

                      o   Exhibit 99.2:  Annual Report of the Firm of
                          Accountants.

          (b)    Current Reports on Form 8-K filed during the last
          quarter ending December 31, 2002:


          Date of Current Report             Item Reported
          ----------------------             -------------

          September 25, 2002        Monthly report sent to certificateholders
                                    with the September 2002 distribution

          October 25, 2002          Monthly report sent to certificateholders


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<PAGE>


                                    with the October 2002 distribution

          November 25, 2002         Monthly report sent to certificateholders
                                    with the November 2002 distribution

          (c)    See subparagraph (a)(3) above.

          (d)    Not applicable. See the Relief Letter.


                                      8
<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.

                                    CWMBS, INC.,
                                    ALTERNATIVE LOAN TRUST, 2002-4, MORTGAGE
                                    PASS-THROUGH CERTIFICATES, SERIES 2002-6

                                    By:  Countrywide Home Loans Servicing LP,
                                         as Master Servicer*

                                    By:  Countrywide GP, Inc.


                                    By:  /s/ Joseph M. Candelario
                                         ---------------------------
                                         Name:   Joseph M. Candelario
                                         Title:  First Vice President

                                    Date:  March 27, 2003



-----------

*  This Report is being filed by the Master Servicer on behalf of the Trust
   Fund.  The Trust Fund does not have any officers or directors.


                                      9
<PAGE>


                                 CERTIFICATION
                                 -------------


          I, Richard DeLeo, certify that:

          1. I have reviewed this annual report on Form 10-K, and all reports
          on Form 8-K containing distribution and servicing reports filed in
          respect of periods included in the year covered by this annual
          report, of CWMBS, Inc., Alternative Loan Trust 2002-4, Mortgage Pass-
          Through Certificates, Series 2002-6;

          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 trustee by the master servicer under
          the pooling and servicing, or similar, agreement, for inclusion in
          these reports is included in these reports;

          4. I am responsible for reviewing the activities performed by the
          master servicer 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 master servicer has fulfilled its obligations under
          that agreement; and

          5. The reports disclose all significant deficiencies relating to the
          master servicer's compliance with the minimum servicing standards
          based upon the report provided by an independent public accountant,
          after conducting a review in compliance with the Uniform Single
          Attestation Program for Mortgage Bankers or similar procedure, as
          set forth in the pooling and servicing, or similar, agreement, that
          is included in these reports.

          In giving the certifications above, I have reasonably relied on
          information provided to me by the following unaffiliated parties:
          The Bank of New York, as Trustee and Litton Loan Servicing LP.


          Date: March 27, 2003


                                    /s/ Richard De Leo
                                    ------------------
                                    Richard De Leo
                                    Managing Director


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<PAGE>


     SUPPLEMENTAL INFORMATION TO BE FURNISHED WITH REPORTS FILED PURSUANT TO
SECTION 15(d) OF THE ACT BY REGISTRANTS WHICH HAVE NOT REGISTERED SECURITIES
PURSUANT TO SECTION 12 OF THE ACT.

     No such annual report, proxy statement, form of proxy or other soliciting
material has been sent to Certificateholders. See the Relief Letter.


                                      11
<PAGE>


<TABLE>
<CAPTION>

                                 EXHIBIT INDEX

                                                                             Sequential
Exhibit Document                                                             Page Number
----------------                                                             -----------

<S>                                                                          <C>
3(i)       Company's Certificate of Incorporation (Filed as an Exhibit to
           Registration Statement on Form S-3 (File No. 33-63714)) *

3(ii)      Company's By-laws (Filed as an Exhibit to Registration Statement
           on Form S-3 (File No. 33-63714)) *

4          Pooling and Servicing Agreement (Filed as part of the Company's
           Current Report on Form 8-K filed on May 3, 2002)     *

99.1       Annual Statement of the Master Servicer.................................13

99.2       Annual Report of the Firm of Accountants................................15

</TABLE>






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

*     Incorporated herein by reference.


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