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                                 EXHIBIT 10(g)


                                THIRD AMENDMENT
                                       OF
                  USG CORPORATION SUPPLEMENTAL RETIREMENT PLAN

             (As Amended and Restated Effective as of July 1, 1997)


               WHEREAS, USG Corporation Supplemental Retirement Plan (the
          "Plan"), established effective January 1, 1976 and amended from time
          to time, was last amended and restated in its entirety effective as of
          July 1, 1997; and

               WHEREAS, further amendment of the Plan now is considered
          desirable;

               NOW, THEREFORE, pursuant to the authority delegated to the
          undersigned by resolution of the Board of Directors of USG
          Corporation, the Plan be and is further amended, effective November 8,
          2000, as follows:

               1. By adding the following new subsection 3.8 to the Plan:

     "3.8      OFFSET/REDUCTION FOR BENEFITS PROVIDED BY FUNDING ACCOUNTS

     Although the plan is an unfunded, non-qualified compensation arrangement,
funds may be paid to the Participant or contributed to an individual trust
intended to constitute a grantor trust of a Participant under Section 671-678 of
the Internal Revenue Code of 1986, as amended (the "Code") or other funding
account established and maintained by a Participant pursuant to a funding
agreement between the Participant and USG (a "Funding Agreement"). If a
Participant has a Funding Agreement with USG, upon the Participant's death or
termination of employment for any reason, the Participant's Part A Supplemental
Benefits and Part A Supplemental Death Benefits will be offset/reduced to the
extent provided in the Funding Agreement to reflect the value of payments made
to the Participant and his or her grantor trust."

               2. By substituting the following for subsection 5.3 of the Plan:

     "5.3      FUNDING

     Benefits payable under this Plan to a Participant or a Supplemental Plan
Beneficiary shall be paid directly by the Employers from their general assets in
such proportions as the Company shall determine to the extent such benefits are
not paid from a Special Retirement Account (established pursuant to Supplement A
of this Plan) or from a Funding Account (as defined in subsection 3.8) or from a
so-called "rabbi trust", an irrevocable grantor trust the assets of which are
subject to the claims of creditors of the Employers in the event of their
insolvency. The Employers shall not be required to segregate on their books or
otherwise any amount to be used for the payment of benefits under this Plan,
except as to any amounts paid or payable to a Funding Account or to a "rabbi
trust"."





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          IN WITNESS WHEREOF, the Company has caused these presents to be signed
     on its behalf by an officer thereunto duly authorized this 19th day of
     December, 2000.

                                        USG CORPORATION


                                        By:
                                           -------------------------------------
                                           Its: Vice President, Compensation,
                                                Benefits And Administration











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