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                                                             Exhibit 10(iii)A(a)




                                 March 21, 1996




Erwin Zaban
3374 Old Plantation Road, N.W.
Atlanta, Georgia   30327

Dear Erwin:

This letter amends your consulting  agreement with National Service  Industries,
Inc.  dated  December 30, 1991, in accordance  with action taken by the Board of
Directors at its meeting yesterday.

The original  term of the  consulting  agreement  was three  years.  Because the
agreement was suspended while you served as an officer of the  Corporation  from
October,  1992 until September,  1994, the original term was scheduled to expire
in October, 1996.

The term of the consulting  agreement is hereby  extended  through  December 30,
1996. The consulting fees and other terms of the agreement remain unchanged.

                                   Sincerely,




                                   /s/ James S. Balloun
                                   James S. Balloun


AGREED TO AND ACCEPTED
AS OF MARCH 21, 1996:



/s/ Erwin Zaban
ERWIN ZABAN