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                                                             Exhibit 10(iii)A(1)


                                SECOND AMENDMENT
                                     TO THE
                        NATIONAL SERVICE INDUSTRIES, INC.
                  1992 NONEMPLOYEE DIRECTORS' STOCK OPTION PLAN



               THIS  AMENDMENT  made as of January 5, 2000, by National  Service
Industries, Inc. ("NSI");


                       W o I o T o N o E o S o S o E o T o H:


         WHEREAS, the 1992 Nonemployee Directors' Stock Option Plan (the "Plan")
was approved by the Board of Directors of NSI on September 16, 1992,  and by the
stockholders  of NSI on January 6, 1993, and was  subsequently  amended on March
24, 1998; and


         WHEREAS,  pursuant to the power of amendment  set forth in Section 9 of
the Plan and action of the Board of Directors of NSI on January 5, 2000;


         NOW, THEREFORE, the Plan is hereby amended as follows:


          1.  Section  5.2 of the Plan is  amended  by  replacing  "1,000"  with
"1,500", so that Section 5.2 now reads in its entirety as follows:


                  5.2 Number of  Shares.Each  Option granted shall be in respect
                  of a number of Shares equal to 1,500, subject to adjustment as
                  provided in Section 7.


         2. Except as hereby  modified,  the Plan shall remain in full force and
effect.


         IN WITNESS WHEREOF,  the parties hereto have executed this Amendment as
of the day and year first written above.


ATTEST:                                    NATIONAL SERVICE INDUSTRIES, INC.



                                           By: /s/ James S. Balloun
      Secretary                             James S. Balloun
                                            Chairman of the Board, President and
                                            Chief Executive Officer


(CORPORATE SEAL)