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: 333-97873-07
                                             ------------


                  CWMBS, Inc., Alternative Loan Trust 2002-3
               Mortgage Pass-Through Certificates, Series 2002-4
               -------------------------------------------------
            (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 2002-3 (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, Inc., as seller (the "Seller"),
Countrywide Home Loans Servicing LP, as 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 2002-4
(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 2, 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, 2002-3, MORTGAGE
                                 PASS-THROUGH CERTIFICATES, SERIES 2002-4

                                 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.


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<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 2002-3,
             Mortgage Pass-Through Certificates, Series 2002-4;

             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 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


                                      10
<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>
                                 EXHIBIT INDEX


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

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 2, 2002) *

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

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













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

*        Incorporated herein by reference.



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