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                                                           Exhibit 10(iii)A49(b)

                            AMENDMENT AND ADOPTION OF
                        NATIONAL SERVICE INDUSTRIES, INC.
                            EXECUTIVE BENEFITS TRUST

         This Agreement made and entered into as of this ____ day of
___________, 1996, by and among National Service Industries, Inc. (the
"Corporation), Wachovia Bank and Trust Company (the "Trustee") and the following
affiliates of the Corporation - North Bros., Inc., National Service Industries,
Inc. of Georgia, NSI Enterprises, Inc., ZEP Manufacturing Company, and NSI
Services, L.P.:

                              W I T N E S S E T H:

         WHEREAS, the Corporation previously established a trust arrangement
known as the National Service Industries, Inc. Executive Benefits Trust (the
"Trust") in order to ensure that participants and their beneficiaries receive
the benefits which the Corporation and its affiliates are obligated to provide
pursuant to various executive compensation arrangements (collectively, the
"Plans") and to provide for additional funding of the Trust upon a Change in
Control of the Corporation; and

         WHEREAS, effective as of August 31, 1996, the Corporation will
reorganize its operations into several newly-formed subsidiary corporations and
limited partnerships including North Bros., Inc., National Service Industries,
Inc. of Georgia, NSI Enterprises , Inc., ZEP Manufacturing Company, and NSI
Services, L.P. (collectively, referred to as the "Affiliates"); and

         WHEREAS, each Affiliate has assumed the obligation, with respect to
certain eligible employees employed by such Affiliate, to provide benefits under
one or more of the Plans; and

         WHEREAS, each of the Affiliates now desires to adopt and become a party
to the Trust upon the terms set forth herein; and

         WHEREAS, the Corporation desires to amend the Trust in certain respects
to clarify each Affiliate's financial obligation to provide benefits to the
Affiliate's eligible employees under any Plan adopted by such Affiliate;

         NOW, THEREFORE, for and in consideration of the premises and the mutual
covenants contained herein, the parties hereto agree as follows:

                                       1.

         The Corporation authorizes each of the Affiliates to adopt and become a
party to the Trust in accordance with the terms and provisions thereof.


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                                       2.

         Effective as of August 31, 1996, each of the Affiliates hereby adopts
and becomes a party to the Trust and agrees to be bound by all the terms and
provisions thereof.

                                       3.

         Section 4.1 of the Trust is hereby amended by deleting the first
sentence thereof in its entirety and substituting the following:

                  "Immediately upon the occurrence of a Change in Control, the
         Company and each Affiliate shall contribute sufficient cash or
         marketable securities to their respective Benefit Accounts in an amount
         equal to the difference between the assets transferred to this Trust
         pursuant to the Transfer and the amount necessary to pay all benefits
         payable (whether payable currently or on a deferred basis) under all
         Transferred Plans as the Trustee, in its discretion, determines;
         provided, however, any Affiliate shall be required to make
         contributions hereunder only to the extent of such Affiliate's
         obligation under each Plan it has adopted."

                                       4.

         Section 4.2 of the Trust is hereby amended by adding "and any
Affiliate" after "Company" wherever it appears therein.

                                       5.

         Section 4.3 of the Trust is hereby amended by adding "or Affiliate, as
applicable" after "Company" wherever it appears therein and by adding the
following to the end of the section:

         "In the event that any Affiliate fails to transfer funds following
         written demand as provided herein, the Company shall assume the
         Affiliate's obligation to transfer such funds."

                                       6.

         Section 9.4 of the Trust is hereby amended by adding the following to
the end of the section:

         "To the extent any Affiliate has failed to transfer funds required
         under Section 4.3, the Trustee may join such Affiliate in any legal
         action against the Company to compel payment."

                                       7.


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         This Agreement shall be effective as of August 31, 1996. Except as
provided herein, the remaining provisions of the Trust shall remain in full
force and effect.

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

ATTEST:                                     NATIONAL SERVICE INDUSTRIES, INC.

                                            By:
----------------------------                    --------------------------------

ATTEST:                                     NORTH BROS., INC.

                                            By:
----------------------------                    --------------------------------

ATTEST:                                     NATIONAL SERVICE INDUSTRIES, INC. OF
                                                     GEORGIA

                                            By:
----------------------------                    --------------------------------

ATTEST:                                     NSI ENTERPRISES, INC.

                                            By:
----------------------------                    --------------------------------

ATTEST:                                     ZEP MANUFACTURING COMPANY

                                            By:
----------------------------                    --------------------------------

ATTEST:                                     NSI SERVICES, L.P.

                                            By:
----------------------------                    --------------------------------

ATTEST:                                     WACHOVIA BANK AND TRUST COMPANY,
                                                     AS TRUSTEE

                                            By:
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