Exhibit 10(iii)A56(c)

                               AMENDMENT NO. 2 TO
                        NATIONAL SERVICE INDUSTRIES, INC.
                  NONEMPLOYEE DIRECTOR DEFERRED STOCK UNIT PLAN

         This Amendment is made as of the 31st day of December, 1997, by
National Service Industries, Inc. (the "Corporation").

                              W I T N E S S E T H:

         WHEREAS, the Corporation previously established and amended the
National Service Industries, Inc. Nonemployee Director Deferred Stock Unit Plan
(the "Plan") for the benefit of directors of the Corporation who are not
employees of the Corporation or any Subsidiary (as defined in the Plan); and

         WHEREAS, pursuant to the power of amendment contained in Section 7.1 of
the Plan, by action of the Board of Directors of the Corporation taken December
17, 1997 and effective on the date hereof, the Plan is hereby amended as
follows:

                                       1.

         Article 5 of the Plan is hereby amended, effective December 31, 1997,
by renumbering Section 5.5 as 5.6 and inserting the following as Section 5.5:

                  5.5      Merger with Deferred Compensation Plan. The account
         of each Eligible Director who participates in the Directors' Deferred
         Compensation Plan shall be credited as of the close of business on
         December 31, 1997, with the number of Deferred Stock Units (rounded to
         the nearest hundredth) equal to such Eligible Director's account
         balance in the Directors' Deferred Compensation Plan as of that date
         divided by the Fair Market Value.

                                       2.

         Except as provided herein, the provisions of the Plan shall remain in
full force and effect.

         IN WITNESS WHEREOF, the parties hereto have executed this Amendment No.
2 as of the day and year first written above.


ATTEST:                             NATIONAL SERVICE INDUSTRIES, INC.



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