Exhibit (15)



May 4, 1999


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,  and
33-65383 on Form S-8 its Form 10-Q for the quarter  ended March 31, 1999,  which
includes  our report  dated April 15, 1999,  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