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                                  EXHIBIT 10.18

                                    YEAR 2003

                                     ANNUAL
                              MANAGEMENT INCENTIVE
                                     PROGRAM

                                 USG CORPORATION

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                                     PURPOSE

To enhance USG Corporation's ability to attract, motivate, reward and retain key
employees of the Corporation and its operating subsidiaries and to align
management's interests with those of the Corporation's stockholders by providing
incentive award opportunities to managers who make a measurable contribution to
the Corporation's business objectives.

                                  INTRODUCTION

This Annual Management Incentive Program (the "Program") is in effect from
January 1, 2003 through December 31, 2003.

                                   ELIGIBILITY

Individuals eligible for participation in this Program are those officers and
other key employees occupying management positions in Broadband 11 or higher.
Employees who participate in any other annual incentive program of the
Corporation or any of its subsidiaries are not eligible to participate in this
Program but could be considered for special awards.

                                      GOALS

For the 2003 Annual Management Incentive Program, Consolidated Net Earnings and
consolidated, subsidiary and profit center Strategic Focus Targets will be
determined by the Compensation and Organization Committee of the USG Board of
Directors (the "Committee") after considering recommendations submitted from
management of USG Corporation and the Operating Subsidiaries.

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                                  AWARD VALUES

For the Annual Management Incentive Program, position target incentive values
are based on level of accountability and are expressed as a percent of approved
annualized salary. Resulting award opportunities represent a fully competitive
incentive opportunity for 100% (target) achievement of goals:

<TABLE>
<CAPTION>
                               POSITION TITLE OR
                            SALARY REFERENCE POINT                                   POSITION TARGET INCENTIVE
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<S>                                                                                  <C>
-    Chairman & CEO, USG Corporation                                                            70%
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-    Executive Vice President & Chief Financial Officer, USG Corporation                        50%

-    Senior Vice President, USG Corporation & President Building Systems

-    Senior Vice President Marketing & Corporate Strategy, USG Corporation and
      President International

-    Senior Vice President & General Counsel, USG Corporation

-    Senior Vice President Financial Operations, USG Corporation

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-    Vice President Human Resources, USG Corporation                                            45%

-    Vice President Communications, USG Corporation

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-    Vice President, USG Corporation & President & COO, L & W Supply Corp.                      40%

-    Vice President Research & Technology, USG Corporation

-    Vice President & Chief Information Officer, USG Corporation

-    Vice President & Controller, USG Corporation

-    Vice President International & Technology, USG Corporation

-    Vice President & Treasurer, USG Corporation

-    Vice President Comp., Benefits & Admin., USG Corporation

-    Corporate Secretary & Associate General Counsel, USG Corporation

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-    Position Reference Point: $172,500 and over                                                35%

-    Position Reference Point: $158,460 - $172,499                                              30%

-    Position Reference Point: $144,480 - $158,459                                              25%

-    Position Reference Point: $129,720 - $144,479                                              20%

-    Position Reference Point: $115,560 - $129,719                                              15%

-    Position Reference Point: $101,760 - $115,559                                              10%
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</TABLE>

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     AWARDS

     Incentive awards for all participants in the 2003 Annual Management
     Incentive Program will be reviewed and approved by the Committee. For all
     participants, the annual incentive award par opportunity is the annualized
     salary in effect at the beginning of the calendar year (March 1, 2003 of
     the calendar year for the sixteen most senior executives) multiplied by the
     applicable position target incentive value percent.

     Incentive awards for 2003 will be based on a combination of the following
     elements:

I.   CONSOLIDATED NET EARNINGS 50% OF INCENTIVE

     Consolidated Net Earnings will be as reported on the Corporation's year-end
     financial statements with adjustments for significant non-operational
     charges. Such adjustments have in the past been for Fresh Start Accounting,
     asbestos, restructuring charges, bankruptcy expenses and the cumulative
     impact of new accounting pronouncements (goodwill impairment). For 2003,
     likely adjustments would include bankruptcy expenses and FAS #143. For all
     participants, this portion of the award represents 50% of the incentive
     par. This portion of the award will be paid from a pool funded by
     Consolidated Net Earnings results according to the following schedule:

      $0 to $50 Million Net Earnings       2.50% of this tier will fund the pool

      $51 to $150 Million Net Earnings     2.25% of this tier will fund the pool

      $151 to $400 Million Net Earnings    1.75% of this tier will fund the pool

      $401 Million and above               1.00% of this tier will fund the pool

     Each tier of earnings is calculated separately and added together to
     determine the total pool. This amount is then divided by the total plan par
     (sum of each individual participant's Net Earnings par, or 50% of each
     participant's total par). The factor derived from this method is then
     applied to each participant's Net Earnings par to determine the individual
     award for this segment. There is no maximum award in this segment.

II.  STRATEGIC FOCUS TARGETS: 50% OF INCENTIVE

     Strategic Focus Targets will be measurable, verifiable and derived from the
     formal strategic planning process . For 2003, Strategic Focus Targets will
     include Overhead Reduction, Working Capital Reduction, Cost Reduction,
     Customer Satisfaction and Business Unit Operating Profit. The award
     adjustment factor for this segment will range from 0.5 (after achieving a
     minimum threshold performance level) to 2.0 for maximum attainment. The
     weighting on any individual Strategic Focus Target will be in 5% increments
     and not be less than 10%. The weighting of all assigned Strategic Focus
     Targets will equal 50% of the individual's total par.

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                         WEIGHTINGS OF PROGRAM ELEMENTS

     All participants in this Program, including the sixteen most senior
     executives, will have the same overall weightings, 50% on Consolidated Net
     Earnings and 50% on Strategic Focus Targets.

                                 SPECIAL AWARDS

     In addition to the incentive opportunity provided by this Program, a
     special award may be recommended for any participant or non-participant,
     other than a Corporation Officer, who has made an extraordinary
     contribution to the Corporation's welfare or earnings.

                               GENERAL PROVISIONS

     1.   The Compensation and Organization Committee of the USG Board of
          Directors reserves the right to adjust award amounts either up or down
          based on its assessment of the Corporation's overall performance
          relative to market conditions.

     2.   The Committee shall review and approve the awards recommended for
          officers and other employees who are eligible participants in the 2003
          Annual Management Incentive Program. The Committee shall submit to the
          Board of Directors, for their ratification, a report of the awards for
          all eligible participants including corporate officers approved by the
          Committee in accordance with the provisions of the Program.

     3.   The Committee shall have full power to make the rules and regulations
          with respect to the determination of achievement of goals and the
          distribution of awards. No awards will be made until the Committee has
          certified financial achievements and applicable awards in writing.

     4.   The judgement of the Committee in construing this Program or any
          provisions thereof, or in making any decision hereunder, shall be
          final and conclusive and binding upon all employees of the Corporation
          and its subsidiaries whether or not selected as beneficiaries
          hereunder, and their heirs, executors, personal representatives and
          assignees.

     5.   Nothing herein contained shall limit or affect in any manner or degree
          the normal and usual powers of management, exercised by the officers
          and the Board of Directors or committees thereof, to change the duties
          or the character of employment of any employee of the Corporation or
          to remove the individual from the employment of the Corporation at any
          time, all of which rights and powers are expressly reserved.

     6.   The awards made to employees shall become a liability of the
          Corporation or the appropriate subsidiary as of December 31, 2003 and
          all payments to be made hereunder will be made as soon as practicable
          after said awards have been approved by the Committee.

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                            ADMINISTRATIVE GUIDELINES

     1.   Award values will be based on annualized salary in effect for each
          qualifying participant at the beginning of the year (March 1, 2003 for
          the sixteen most senior executives). Any change in duties, dimensions
          or responsibilities of a current position resulting in an increase or
          decrease in salary range reference point or market rate will result in
          pro-rata incentive award. Respective reference points, target
          incentive values or goals will be applied based on the actual number
          of full months of service at each position.

     2.   As provided by the Program, no award is to be paid to any participant
          who is not a regular full-time employee, (or a part time employee as
          approved by the Vice President Human Resources, USG Corporation) in
          good standing at the end of the calendar year to which the award
          applies. However, if an eligible participant with three (3) or more
          months of active service in the Program year subsequently retires,
          becomes disabled, dies, is discharged from the employment of the
          Company without cause, or is on an approved unpaid leave, the
          participant (or beneficiary) may be recommended for an award which
          would otherwise be payable based on goal achievement, prorated for the
          actual months of active service during the year.

     3.   Employees participating in any other incentive or bonus program of the
          Corporation or a Subsidiary who are transferred during the year to a
          position covered by the Annual Management Incentive Program will be
          eligible to receive a potential award prorated for actual full months
          of service in the two positions with the respective incentive program
          and target incentive values to apply. For example, a Marketing Manager
          promoted to Director, Marketing on August 1, will be eligible to
          receive a pro-rata award for seven months based on the Marketing
          Manager Plan provisions and values, and for five months under the
          Annual Management Incentive Program provisions and target incentive
          values.

     4.   In the event of transfer of an employee from an assignment which does
          not qualify for participation in any incentive or bonus plan to a
          position covered by the Annual Management Incentive Program, the
          employee is eligible to participate in the Annual Management Incentive
          Program with any potential award prorated for the actual months of
          service in the position covered by the Program during the year. A
          minimum of three months of service in the eligible position is
          required.

     5.   Participation during the current Program year for individuals employed
          from outside the Corporation is possible with any award to be prorated
          for actual full months of service in the eligible position. A minimum
          of three full months of eligible service is required for award
          consideration.

     6.   Exceptions to established administrative guidelines can only be made
          by the Committee.

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