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                                                           EXHIBIT 10(iii)(A)(3)

                             THIRD AMENDMENT TO THE
                              AMENDED AND RESTATED
                                RIGHTS AGREEMENT

         THIS THIRD AMENDMENT (the "Third Amendment"), dated as of April 1,
2003, is between National Service Industries, Inc., a Delaware corporation (the
"Company"), and EquiServe, L.P. (as successor-in-interest to First Chicago Trust
Company of New York), as Rights Agent (the "Rights Agent").

         WHEREAS, the Company and the Rights Agent are parties to an Amended and
Restated Rights Agreement dated as of December 17, 1997, as amended on April 30,
1998 and as further amended on January 6, 1999 (the "Rights Agreement").

         WHEREAS, NS ACQUISITION CORP., a Delaware corporation ("Buyer"), and
the Company propose to enter into an Agreement and Plan of Merger pursuant to
which Buyer will be merged with and into the Company and each share of common
stock of the Company will be converted into the right to receive a specified
amount of cash.

         WHEREAS, pursuant to Section 28 of the Rights Agreement, the Board of
Directors of the Company has determined that an amendment to the Rights
Agreement as set forth herein is necessary and desirable to reflect the
foregoing and certain other matters, and the Company and the Rights Agent desire
to evidence such amendment in writing.

         NOW, THEREFORE, in consideration of the premises and the mutual
agreements herein set forth, the parties hereto hereby agree as follows:

         1.       Amendment of Section 1. Section 1 of the Rights Agreement is
amended by inserting the following as a new paragraph at the end of Section 1:

                  "In addition, notwithstanding anything in this Agreement to
         the contrary, (i) neither NS Acquisition Corp., a Delaware corporation
         ("Buyer"), nor any Affiliate or Associate of Buyer, shall be deemed to
         be an Acquiring Person by virtue of the execution of the Agreement and
         Plan of Merger, to be entered into as of April 1, 2003, by and between
         Buyer and the Company, as it may be amended or supplemented from time
         to time in accordance with its terms (the "Merger Agreement"), or by
         virtue of any of the transactions contemplated by the Merger Agreement
         and (ii) no Stock Acquisition Date or Distribution Date or Triggering
         Event shall be deemed to occur by virtue of the execution of the Merger
         Agreement or by virtue of any of the transactions contemplated by the
         Merger Agreement."

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         2.       Amendment of Section 24. Section 24 of the Rights Agreement is
amended by inserting the following as a new paragraph at the end of Section 24:

                  "In addition, notwithstanding anything in this Agreement to
         the contrary, this Agreement shall terminate and the Rights shall
         expire at the Effective Time (as defined in the Merger Agreement)."

         3.       Effectiveness. This Amendment shall be deemed effective as of
April 1, 2003, as if executed on such date. Except as expressly amended hereby,
all of the terms and provisions of the Rights Agreement are and shall remain in
full force and effect and shall be otherwise unaffected hereby.

         4.       Governing Law. This Amendment shall be deemed to be a contract
made under the laws of the State of Delaware and for all purposes shall be
governed by and construed in accordance with the laws of such State applicable
to contracts to be made and performed entirely within such State.

         5.       Counterparts. This Amendment may be executed in any number of
counterparts, each of such counterparts shall for all purposes be deemed to be
an original, and all such counterparts shall together constitute but one and the
same instrument.

         6.       Severability. If any term, provision, covenant or restriction
of this Third Amendment is held by a court of competent jurisdiction or other
authority to be invalid, void or unenforceable, the remainder of the terms,
provisions, covenants and restrictions of this Third Amendment shall remain in
full force and effect and shall in no way be affected, impaired or invalidated.

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         IN WITNESS WHEREOF, the parties hereto have caused this Third Amendment
to be duly executed as of the date first above written.


                                         NATIONAL SERVICE INDUSTRIES, INC.


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                                         Name:
                                         Title:




                                         EQUISERVE, L.P.


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                                         Name:
                                         Title:




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