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                                                           EXHIBIT 10(iii)A4(c)

                                 AMENDMENT NO. 2
                                     TO THE
                 SUPPLEMENTAL RETIREMENT PLAN FOR EXECUTIVES OF
                        NATIONAL SERVICE INDUSTRIES, INC.

         THIS AMENDMENT made as of this _____ day of _______________, 1996, by
National Service Industries, Inc. ("NSI");

                              W I T N E S S E T H:

         WHEREAS, NSI has previously established the Supplemental Retirement
Plan for Executives of National Service Industries, Inc. (the "Plan") for the
exclusive benefit of its eligible employees and their beneficiaries; and

         WHEREAS, effective as of August 31, 1996, NSI will reorganize its
operations into several newly-formed corporations and limited partnerships; and

         WHEREAS, NSI desires to amend the Plan in connection with the
reorganization; and

         WHEREAS, pursuant to the power of amendment contained in Section 11.1
of the Plan, the Plan is hereby amended as follows:

                                       1.

         Section 1.1(o) of the Plan is hereby amended by deleting such section
in its entirety and substituting the following:

                  "1.1(o) Company: Company shall mean National Service
         Industries, Inc. (or its successor or successors). Affiliated or
         related employers are permitted to adopt the Plan and shall be known as
         "Adopting Employers." To the extent required by certain provisions
         (e.g., determining Average Monthly Compensation, Credited Service and
         Service Date), references to the Company shall include the Adopting
         Employer of the Participant. Adopting Employers are listed on Schedule
         1."

                                       2.

         Section 1.1(w) of the Plan is hereby amended by deleting such section
in its entirety and substituting the following:

                  "(w) Executive: Any person who, on or after the Effective
         Date, is classified as an executive officer of the Company covered by a
         bonus arrangement and who is receiving remuneration for personal
         services rendered to the Company (or would be receiving such
         remuneration except for an Authorized Leave of Absence), and any other
         officer of the Company (or an Adopting Employer) designated by the
         Chief Executive Officer of the

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Company as eligible to participate in the Plan and who is listed on an Appendix
attached hereto."

                                       3.

         Section 5.1 of the Plan is hereby amended by deleting such section in
its entirety and substituting the following:

                  "5.1 Payment of Costs and Expenses: All costs of providing the
         benefits under the Plan and the expenses thereof, including the cost of
         the Committee and the Administrator and any Actuary, shall be paid from
         the general assets of the Company (or with respect to Participants
         employed by an Adopting Employer, from the general assets of such
         Adopting Employer)."

                                       4.

         Article X of the Plan is hereby amended by deleting such article in its
entirety and substituting the following:

                                   "Article X
                                      Trust

         "The benefits provided by this Plan shall be unfunded. All amounts
         payable under this Plan to a Participant shall be paid from the general
         assets of the employer which principally employs the Participant (the
         "Obligated Employer"), and nothing contained in this Plan shall require
         the Obligated Employer to set aside or hold in trust any amounts or
         assets for the purpose of paying benefits to Participants. This Plan
         shall create only a contractual obligation on the part of the Obligated
         Employer and Participants shall have the status of general unsecured
         creditors of the Obligated Employer under the Plan with respect to
         amounts of Compensation they defer hereunder or any other obligation of
         the Obligated Employer to pay benefits pursuant hereto. Any funds of
         the Obligated Employer available to pay benefits pursuant to the Plan
         shall be subject to the claims of general creditors of the Obligated
         Employer, and may be used for any purpose by the Obligated Employer.

                  Notwithstanding the preceding paragraph, the Obligated
         Employer may at any time transfer assets to a trust for purposes of
         paying all or any part of its obligations under this Plan. However, to
         the extent provided in the trust only, such transferred amounts shall
         remain subject to the claims of general creditors of the Obligated
         Employer. To the extent that assets are held in a trust when a
         Participant's benefits under the Plan become payable, the Plan
         Administrator shall direct the trustee to pay such benefits to the
         Participant from the assets of the trust."

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                                       5.

         Article XII of the Plan is hereby amended by adding the following new
section 12.8:

                  "12.8 Guarantee of Performance: In consideration of each
         Participant's performance of valuable services that inure to the
         financial benefit of the Company, the Company does hereby agree to
         perform all of the obligations and responsibilities and pay any
         benefits due and owing to a Participant under the Plan if the Obligated
         Employer (as defined in Article X) designated to perform such
         obligations and responsibilities or pay such benefits fails or is
         unable to do so."

                                       6.

         The Plan is hereby amended by incorporating the following as Schedule
1:

                                   "Schedule 1
                               Adopting Employers

         North Bros, Inc.
         National Service Industries, Inc. of Georgia
         NSI Enterprises, Inc.
         Zep Manufacturing Company
         NSI Services, L.P."

                                       7.

         This Amendment shall be effective August 31, 1996.

                                       8.

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

         IN WITNESS WHEREOF, NSI has caused this Amendment No. 2 to be executed
by its duly authorized corporate officer and is hereby accepted the same as of
the date and year first written above.


ATTEST:                                     NATIONAL SERVICE INDUSTRIES, INC.


By:                                         By:
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