November 4, 1997


USG Corporation
125 South Franklin Street
Chicago, Illinois  60606


Gentlemen:

We are aware that USG Corporation has  incorporated by reference into previously
filed  Registration  Statement  Numbers  33-40136  and  33-64217 on Form S-3 and
33-22581,  as  amended,  33-22930,  33-36303,  33-52573,  33-52715,  33-  63554,
33-65383,  333-29137,  and  333-34147  on Form S-8 its Form 10-Q for the quarter
ended  September  30, 1997,  which  includes our report dated  October 21, 1997,
covering  the  unaudited  condensed  financial  information  contained  therein.
Pursuant to Regulation C of the  Securities  Act of 1933,  these reports are not
considered  a part of the  registration  statement  prepared or certified by our
firm or reports prepared or certified by our firm within the meaning of Sections
7 and 11 of the Act.


Very truly yours,

/s/ ARTHUR ANDERSEN LLP
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ARTHUR ANDERSEN LLP