EXHIBIT 10

                        FOURTH AMENDMENT
                   Dated as of March 17, 1995
                               to
              AMENDED AND RESTATED CREDIT AGREEMENT
                     Dated as of May 6, 1993


          This FOURTH AMENDMENT (this "Fourth Amendment") dated
as of March 17, 1995 is entered into among USG CORPORATION (the
"Company"), USG INTERIORS, INC. ("Interiors") (the Company and
Interiors being sometimes collectively referred to herein as the
"Borrowers"), the FINANCIAL INSTITUTIONS LISTED ON THE SIGNATURE
PAGES HEREOF (collectively referred to herein, together with
their respective successors and assigns, as the "Senior Lenders"
and individually as a "Senior Lender"), BANKERS TRUST COMPANY,
CHEMICAL BANK and CITIBANK, N.A. ("Citibank"), in their
capacities as agents for the Senior Lenders hereunder (in such
capacities, the "Agents"), and CITIBANK, in its separate capacity
as administrative agent for the Senior Lenders hereunder (in such
capacity, the "Administrative Agent").  

          PRELIMINARY STATEMENTS.  (1)  The Borrowers, the Senior
Lenders, the Agents and the Administrative Agent have entered
into the Amended and Restated Credit Agreement dated as of May 6,
1993 (as amended pursuant to that certain First Amendment dated
as of August 1, 1993 (the "First Amendment"), that certain Second
Amendment dated as of January 31, 1994 (the "Second Amendment")
and that certain Third Amendment dated as of August 11, 1994 (the
"Third Amendment"), the "Credit Agreement") and have agreed to
further amend the Credit Agreement as hereinafter set forth.

          (2)  Capitalized terms used herein and not otherwise
defined herein shall have the meanings ascribed to such terms in
the Credit Agreement.  Unless referring to a section of this
Fourth Amendment, all section references contained herein are
references to section numbers as they appear in the Credit
Agreement.

          SECTION 1.  Amendments to the Credit Agreement.  Upon
the occurrence of the "Fourth Amendment Effective Date" (as
defined in Section 3 below), the Credit Agreement is amended as
follows:

          1.1.  Amendments to Defined Terms.

          (a)  Section 1.01 of the Credit Agreement is hereby
amended as follows:

               (i)  The defined term "Cash Sweep Termination
     Date" is deleted in its entirety.

               (ii)  The following defined term is inserted in
     Section 1.01 immediately following the defined term "CGC
     Permitted Indebtedness":

                    "CGC Stock Purchase Payments" shall have the
          meaning ascribed to such term in Section 8.05(vii).

               (iii)  The defined term "Restricted Subsidiary" is
     amended and restated in its entirety as follows:

                    "Restricted Subsidiary" shall mean (i) each
          Subsidiary of the Company which has executed any of the
          Subsidiary Guaranties, (ii) each Subsidiary of the
          Company the capital stock of which is subject to the
          Company Pledge Agreement or any of the Subsidiary
          Pledge Agreements, (iii) Donn Canada Limited, a
          corporation organized under the laws of Canada, (iv)
          C.N.G. Distribution Limited, a corporation organized
          under the laws of Canada, and (v) CGC.

          (b)  Section 1.02 of the Credit Agreement is hereby
amended to delete the term "Cash Sweep Termination Date" in its
entirety.

          1.2.  Amendments to Mandatory Prepayment of Cash
Available for Sweep.  Section 2.06(b)(i) of the Credit Agreement
is amended as follows:

          (a)  Section 2.06(b)(i)(A) is hereby amended to delete
the following parenthetical phrases which appear therein:  (i)
"(unless the Cash Sweep Termination Date has occurred on or
before such Test Date)" and (ii) "(unless the Cash Sweep
Termination Date has occurred on or before the immediately
preceding Test Date)".

          (b)  Section 2.06(b)(i)(B) is hereby amended to:

               (i)  Delete in its entirety the definition of the
     term "Cash Sweep Termination Date".

               (ii)  Insert the word "Unrestricted" in the
     definition of the term "Minimum Liquidity" immediately
     before the words "Retained Amounts" therein.

               (iii)  Amend and restate the definition of the
     term "Sweep Percentage" in its entirety as follows:

                    "'Sweep Percentage' means (i) 100% for the
          Test Dates occurring in 1995 and 1996, (ii) 90% for
          each of the Test Dates occurring in 1997 and 1998, and
          (iii) 85% for the Test Date occurring in 1999 and any
          subsequent Test Dates; provided, that the Sweep
          Percentage shall be 50% for any Test Date for which the
          ratio of "Debt" as of the last day of the immediately
          preceding Fiscal Year to "EBITDA" for such Fiscal Year
          (as such terms are defined in Section 9.01 hereof, but
          without reference to Section 9.10 hereof) was less than
          4.0 to 1.0; and provided, further, that the Sweep
          Percentage shall be 0% for any Test Date on which the
          aggregate principal amount of outstanding Term Loans is
          less than or equal to $150,000,000."

          1.3.  Amendment to Mandatory Prepayments.  Section
2.06(b) of the Credit Agreement is hereby further amended to
insert the following subsection (iii):

               "(iii)  Certain Public Debt Investments.  So long
     as (and only to the extent that) the outstanding principal
     amount of the Term Loans is greater than $150,000,000, the
     Company shall make or cause to be made a mandatory
     prepayment of the Term Loans, applied in the order of
     maturity, in an amount equal to the amount of each
     Investment in Public Debt made under Section 8.03(ix)(b)
     hereof, such mandatory prepayment to be made at any time on
     or after the making of such Investment, but in no event
     later than the tenth (10th) day following the last day of
     the calendar quarter in which such Investment was made."

          1.4.  Amendments to Reporting Covenant.  Section 6.01
of the Credit Agreement is hereby amended as follows:

          (a)  Section 6.01(a) of the Credit Agreement is amended
to add the following proviso at the end thereof:

     "provided, that the Company shall have no obligation to
     deliver the foregoing documents for any fiscal month for
     which the ratio of 'Debt' as of the last day of the
     immediately preceding fiscal quarter to 'EBITDA' for the 12-
     month period ending on the last day of such fiscal quarter
     (as such terms are defined in Section 9.01 hereof, but
     without reference to Section 9.10 hereof) was less than 4.0
     to 1.0;"

          (b)  Section 6.01(b) of the Credit Agreement is amended
to insert the following immediately after the word "above" in the
second line thereof:  "or pursuant to clause (c) below".

          1.5.  Amendments to Investments Covenant.  Section 8.03
of the Credit Agreement is hereby amended as follows:

          (a)  Section 8.03(viii) of the Credit Agreement is
amended to delete clause (E) thereof in its entirety.

          (b)  Section 8.03 of the Credit Agreement is further
amended to delete clauses (ix) and (x) thereof in their entirety
and to substitute therefor the following:

               "(ix)  Investments in Public Debt, in order to
     effectuate the prepayment (or defeasance, subject to
     restrictions acceptable to the Agents) of such Public Debt,
     made with (a) Unrestricted Retained Amounts or (b) other
     funds, provided that with respect to Investments under this
     clause (b), Available Liquidity (as defined in Section
     2.06(b)(i) hereof but calculated as of the time of such
     Investment and after giving effect thereto and to the
     mandatory prepayment of the Term Loans required as a result
     thereof under Section 2.06(b)(iii)) shall equal or exceed
     $100,000,000;

               (x)  Investments, not otherwise described in
     clauses (i) through (ix) above, in 10-1/4% Senior Notes, in
     order to effectuate the prepayment (or defeasance, subject
     to restrictions acceptable to the Agents) thereof, not
     exceeding $30,000,000 in the aggregate amount at any one
     time outstanding; and

               (xi)  any other Investments not otherwise
     described in clauses (i) through (x) above, not exceeding
     Forty Million Dollars ($40,000,000) in the aggregate at any
     one time outstanding; provided, that Investments in Public
     Debt under this clause (xi) shall not at any one time exceed
     an aggregate amount of $5,000,000."

          1.6.  Amendment to Restricted Junior Payments Covenant. 
Section 8.05 of the Credit Agreement is amended to delete clause
(vii) thereof and to substitute therefor the following:

               "(vii)  the purchase, repurchase, acquisition or
     redemption (as applicable) of the publicly owned common
     stock of CGC by (A) CGC, in an amount not to exceed 10% of
     its total outstanding shares of common stock in any single
     calendar year and/or (B) the Company (each payment by the
     Company for such stock being a "CGC Stock Purchase
     Payment")."

          1.7.  Amendment to Capital Expenditures Covenant. 
Section 9.08 of the Credit Agreement is hereby amended to (a)
insert the words "Unrestricted Retained Amounts" in clause (v)
thereof, and (b) insert the following at the end of such Section
9.08:

     "For the purposes of the foregoing, so long as the aggregate
     outstanding principal amount of Term Loans is greater than
     $150,000,000, all CGC Stock Purchase Payments made by the
     Company during any Fiscal Year shall be deemed Capital
     Expenditures and shall reduce the aggregate amount of
     Capital Expenditures permitted in such Fiscal Year
     accordingly; provided, that the Company may make CGC Stock
     Purchase Payments during a Fiscal Year in excess of the then
     remaining amount of Capital Expenditures permitted
     hereunder, in which case no further Capital Expenditures may
     be made by the Company and its Subsidiaries during such
     Fiscal Year and the amount of CGC Stock Purchase Payments
     made in excess of such remaining amount of permitted Capital
     Expenditures shall be allocated to the following Fiscal Year
     (and, if necessary, succeeding Fiscal Years).  It is
     understood that, once the aggregate outstanding principal
     amount of Term Loans is less than or equal to $150,000,000,
     all such CGC Stock Purchase Payments shall be deemed not to
     have been Capital Expenditures ab initio, and the Company
     and its Subsidiaries shall be entitled to the use of Base
     Capital Expenditures Allowances under clause (viii) above
     for prior Fiscal Years without regard to any deemed use on
     account of CGC Stock Purchase Payments."

          SECTION 2.  Release of Capital Stock of CGC and USG
Interiors (Donn) S.A.  Pursuant to Section 12.01(c)(ii) of the
Credit Agreement, the Requisite Senior Lenders hereby direct the
Collateral Trustee to (i) release the capital stock of each of
CGC and USG Interiors (Donn) S.A. ("Donn") from the Liens granted
to the Collateral Trustee pursuant to the applicable Subsidiary
Pledge Agreements executed by Foreign Investments, (ii) deliver
the stock certificates and stock powers relating to such
Subsidiaries to the Company, and (iii) cancel and terminate the
Subsidiary Pledge Agreement pursuant to which the capital stock
of Donn was pledged.

          SECTION 3.  Conditions Precedent to Effectiveness. 
This Fourth Amendment shall become effective as of the date (the
"Fourth Amendment Effective Date") on which each of the following
conditions precedent shall have occurred:

          (a)  Documentation.  The Agents shall have received all
of the following:

          (i)  Counterparts of this Fourth Amendment executed by
both of the Borrowers, the Agents, the Administrative Agent and
Senior Lenders whose Term Loans and Revolving Loan Commitments
aggregate 66-2/3% or more of the sum of the then aggregate unpaid
principal balance of the Term Loans and the then aggregate
principal amount of the Revolving Loan Commitments;

          (ii)  Reaffirmations of Guaranties executed by the
Company and each Subsidiary party to a Subsidiary Guaranty, in
form and substance reasonably satisfactory to the Agents and
counsel for the Agents;

          (iii)  The opinion of the Assistant General Counsel of
the Company and Interiors relating to such matters as the Agents
deem appropriate and in form and substance reasonably
satisfactory to the Agents and counsel for the Agents;

          (iv)  A certificate of the Secretary or Assistant
Secretary of the Company certifying (A) the names and true
signatures of the incumbent officers of the Company authorized to
sign this Fourth Amendment and all other Loan Documents executed
by the Company in connection herewith and (B) the resolutions of
the Company's Board of Directors approving and authorizing the
execution, delivery and performance of this Fourth Amendment and
all other Loan Documents executed by the Company in connection
herewith; and

          (v)  A certificate of the Secretary or Assistant
Secretary of Interiors certifying (A) the names and true
signatures of the incumbent officers of Interiors authorized to
sign this Fourth Amendment and all other Loan Documents executed
by Interiors in connection herewith and (B) the resolutions of
Interiors' Board of Directors approving and authorizing the
execution, delivery and performance of this Fourth Amendment and
all other Loan Documents executed by Interiors in connection
herewith.

          (b)  No Events of Default.  No Event of Default or
Potential Event of Default shall have occurred and be continuing.

          SECTION 4.  Confirmation of Credit Agreement.  Except
as herein expressly amended, the Credit Agreement is ratified and
confirmed in all respects and shall remain in full force and
effect in accordance with its terms.  Each reference in the
Credit Agreement to "this Agreement" shall mean the Credit
Agreement as amended by the First Amendment, the Second
Amendment, the Third Amendment and this Fourth Amendment, and as
hereafter amended or restated.

          SECTION 5.  Costs and Expenses.  Each Borrower agrees
to pay on demand all costs and expenses of the Administrative
Agent and the Agents in connection with the preparation,
reproduction, execution and delivery of this Fourth Amendment,
including the reasonable fees and out-of-pocket expenses of
Sidley & Austin, counsel for the Agents.

          SECTION 6.  Successors and Assigns.  This Fourth
Amendment and the other Loan Documents executed in connection
herewith shall be binding upon the parties hereto and thereto and
their respective successors and assigns (including, without
limitation, a receiver, trustee or debtor-in-possession of any of
the Borrowers) and shall inure to the benefit of the parties
hereto and thereto and the successors and permitted assigns of
the Senior Lenders, the Agents and the Issuing Banks.

          SECTION 7.  Execution in Counterparts.  This Fourth
Amendment may be executed and delivered in any number of
counterparts and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall
be deemed to be an original and all of which taken together shall
constitute one and the same original agreement.

          SECTION 8.  Governing Law.  This Fourth Amendment shall
be governed by and construed in accordance with the laws of the
State of New York.

          SECTION 9.  Headings.  Section headings in this Fourth
Amendment are included herein for convenience of reference only
and shall not constitute a part of this Fourth Amendment for any
other purpose.




          IN WITNESS WHEREOF, the parties hereto have caused this
Fourth Amendment to be executed by their respective officers
thereunto duly authorized as of the date first above written.


                              USG CORPORATION


                              By____________________________
                                Title:


                              USG INTERIORS, INC.


                              By____________________________
                                Title:

                              CITIBANK, N.A., 
                               as Administrative Agent, as an
                               Agent and as a Senior Lender


                              By                          
                                Title:

                              BANKERS TRUST COMPANY, as an
                               Agent and as a Senior Lender


                              By                          
                                Title:

                              CHEMICAL BANK, as an Agent
                               and as a Senior Lender


                              By                          
                                Title: