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

                                  SCHEDULE 13G

                   Under the Securities Exchange Act of 1934


                               Mirant Corporation
--------------------------------------------------------------------------------
                                (Name of Issuer)

                                  Common Stock
--------------------------------------------------------------------------------
                         (Title of Class of Securities)

                                    604675108
                        ------------------------------
                                 (CUSIP Number)

                                    12-31-02
--------------------------------------------------------------------------------
            (Date of Event Which Requires Filing of this Statement)


Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

     [X] Rule 13d-1(b)

     [_] Rule 13d-1(c)

     [_] Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting
  person's initial filing on this form with respect to the subject class of
  securities, and for any subsequent amendment containing information which
  would alter the disclosures provided in a prior cover page.


The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).

                               Page 1 of 4 Pages



CUSIP NO.  604675108                  13G
         -------------
--------------------------------------------------------------------------------
 1.   Name of Reporting Person
      S.S or I.R.S. Identification No. of Above Person

      Barrow, Hanley, Mewhinney & Strauss, Inc.
        752403190
--------------------------------------------------------------------------------
 2.   Check the Appropriate Box If a Member of a Group (See Instructions)
                                                                (a) [_]
                                                                (b) [_]
--------------------------------------------------------------------------------
 3.   SEC Use Only

--------------------------------------------------------------------------------
 4.   Citizenship or Place of Organization

      A Nevada corporation
--------------------------------------------------------------------------------
                     5.   Sole Voting Power
   NUMBER OF                                            86,554
    SHARES         -------------------------------------------------------------
 BENEFICIALLY        6.   Shared Voting Power
   OWNED BY                                             29,197,129
     EACH          -------------------------------------------------------------
  REPORTING          7.   Sole Dispositive Power
    PERSON                                              29,283,683
     WITH          -------------------------------------------------------------
                     8.     Shared Dispositive Power
                                                        --
--------------------------------------------------------------------------------
 9.   Aggregate Amount Beneficially Owned by Each Reporting Person

      29,283,683
--------------------------------------------------------------------------------
10.   Check Box If the Aggregate Amount in Row (9) Excludes Certain Shares
      (See Instructions)
                                                                    [_]
--------------------------------------------------------------------------------
11.   Percent of Class Represented by Amount in Row (9)

      7.25%
--------------------------------------------------------------------------------
12.   Type of Reporting Person (See Instructions)

      IA
--------------------------------------------------------------------------------

                               Page 2 of 4 Pages



SCHEDULE 13G
------------

Item 1(a) Name of Issuer
                Mirant Corporation

     1(b) Address of Issuer's Principal Executive Offices
                1155 Perimeter Center West, Suite 100
                Atlanta, GA 30338

Item 2(a) Name of Person Filing
                Barrow, Hanley, Mewhinney & Strauss, Inc.

     2(b) Address of Principal Business Office or, if none, Residence
                One McKinney Plaza
                3232 McKinney Avenue, 15th Floor
                Dallas, TX 75204-2429

     2(c) Citizenship
                A Nevada corporation

     2(d) Title of Class of Securities
                Common Stock

     2(e) CUSIP Number
                604675108

Item 3.   If this statement is filed pursuant to Rules 13d-1(b) or 13d-2(b):
                The reporting person is an Investment Adviser registered
                under Section 203 of the Investment Advisers Act of 1940.

Item 4.   Ownership:

     4(a) Amount beneficially owned:
                29,283,683

     4(b) Percent of class:
                7.25%

     4(c) Number of shares as to which the person has:

          (i)   Sole power to vote or to direct the vote:
                        86,554


                                Page 3 of 4 Pages




          (ii)  Shared power to vote or to direct the vote:
                        29,197,129

          (iii) Sole power to dispose or to direct the disposition of:
                        29,283,683

          (iv)  Shared power to dispose or to direct the disposition of:
                        --

Item 5.   Ownership of Five Percent or Less of a Class:
                Not Applicable.

Item 6.   Ownership of More than Five Percent on Behalf of Another Person:
                The right to receive or the power to direct the receipt of
                dividends from, or the proceeds from the sale of, the common
                stock is held by certain clients of the reporting person, none
                of which has such right or power with respect to five percent or
                more of the common stock.

Item 7.   Identification and Classification of the Subsidiary which Acquired the
          Security Being Reported on by the Parent Holding Company:
                Not Applicable.

Item 8.   Identification and Classification of Members of the Group:
                Not Applicable.

Item 9.   Notice of Dissolution of a Group:
                Not Applicable.

Item 10.  Certification:

                By signing below the undersigned certifies that, to the best of
                its knowledge and belief, the securities referred to above were
                acquired in the ordinary course of business and were not
                acquired for the purpose of and do not have the effect of
                changing or influencing the control of the issuer of such
                securities and were not acquired in connection with or as a
                participant in any transaction having such purpose or effect.

After reasonable inquiry and to the best of its knowledge and belief, the
undersigned certifies that the information set forth in this statement is true,
complete and correct.

                                       BARROW, HANLEY, MEWHINNEY & STRAUSS, INC.


                                       By: /s/ James P. Barrow
                                           ---------------------------------
                                           Name:  James P. Barrow
                                           Title: President

February 8, 2003


                               Page 4 of 4 Pages