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                                                            Exhibit 10(iii)A(28)


                        INCENTIVE STOCK OPTION AGREEMENT



      THIS AGREEMENT, made as of the 5th day of January, 2000 (the "Grant
Date"), between National Service Industries, Inc., a Delaware corporation (the
"Company"), and ((Name)) (the "Optionee").

      WHEREAS, the Company has adopted the National Service Industries, Inc.
Long-Term Achievement Incentive Plan (the "Plan") in order to provide additional
incentive to certain officers and key employees of the Company and its
Subsidiaries; and

      WHEREAS, the Optionee performs services for one of the Subsidiaries; and

      WHEREAS, the Committee responsible for administration of the Plan has
determined to grant the Option to the Optionee as provided herein.

      NOW, THEREFORE, the parties hereto agree as follows:

      1.    Grant of Option.

            1.1 The Company hereby grants to the Optionee the right and option
(the "Option") to purchase all or any part of an aggregate of ((Amount)) whole
Shares subject to, and in accordance with, the terms and conditions set forth in
this Agreement.

            1.2 The Option is intended to qualify as an Incentive Stock Option
within the meaning of Section 422 of the Code and shall be so construed;
provided, however, that nothing in this Agreement shall be interpreted as a
representation, guarantee, or other undertaking on the part of the Company that
the Option is or will be determined to be an Incentive Stock Option within the
meaning of Section 422 of the Code. To the extent this Option is not treated as
an Incentive Stock Option, it will be treated as a Nonqualified Stock Option.

            1.3 This Agreement shall be construed in accordance and consistent
with, and subject to, the provisions of the Plan (the provisions of which are
incorporated herein by reference) and, except as otherwise expressly set forth
herein, the capitalized terms used in this Agreement shall have the same
definitions as set forth in the Plan.

      2.    Purchase Price.

            The price at which the Optionee shall be entitled to purchase Shares
upon the exercise of the Option shall be $27.6875 per Share.
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      3.    Duration of Option.

            The Option shall be exercisable to the extent and in the manner
provided herein for a period of ten (10) years from the Grant Date (the
"Exercise Term"); provided, however, that the Option may be earlier terminated
as provided in Section 6 hereof.

      4.    Exercisability of Option.

            Unless otherwise provided in this Agreement or the Plan, the Option
shall entitle the Optionee to purchase, in whole at any time or in part from
time to time, ((Para)). Each such right of purchase shall be cumulative and
shall continue, unless sooner exercised or terminated as herein provided during
the remaining period of the Exercise Term.

      5.    Manner of Exercise and Payment.

            5.1 Subject to the terms and conditions of this Agreement and the
Plan, the Option may be exercised by delivery of written notice to the Company,
at its principal executive office. Such notice shall state that the Optionee is
electing to exercise the Option and the number of Shares in respect of which the
Option is being exercised and shall be signed by the person or persons
exercising the Option. If requested by the Committee, such person or persons
shall (i) deliver this Agreement to the Secretary of the Company who shall
endorse thereon a notation of such exercise and (ii) provide satisfactory proof
as to the right of such person or persons to exercise the Option.

            5.2 The notice of exercise described in Section 5.1 shall be
accompanied by the full purchase price for the Shares in respect of which the
Option is being exercised, in cash, by check, or by transferring Shares to the
Company having a Fair Market Value on the day preceding the date of exercise
equal to the cash amount for which such Shares are substituted.

            5.3 Upon receipt of notice of exercise and full payment for the
Shares in respect of which the Option is being exercised, the Company shall,
subject to Section 17 of the Plan, take such action as may be necessary to
effect the transfer to the Optionee of the number of Shares as to which such
exercise was effective.

            5.4 The Optionee shall not be deemed to be the holder of, or to have
any of the rights of a holder with respect to any Shares subject to the Option
until (i) the Option shall have been exercised pursuant to the terms of this
Agreement and the Optionee shall have paid the full purchase price for the
number of Shares in respect of which the Option was exercised, (ii) the Company
shall have issued and delivered the Shares to the Optionee, and (iii) the
Optionee's name shall have been entered as a stockholder of record on the books
of the Company, whereupon the Optionee shall have full voting and other
ownership rights with respect to such Shares.

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      6.    Termination of Employment.

            6.1   In General.

                  If the employment of the Optionee with the Company and its
Subsidiaries shall terminate for any reason, other than for the reasons set
forth in Section 6.2 and 7.2, below, the Option shall continue to be exercisable
(to the extent the Option was vested and exercisable on the date of the
Optionee's termination of employment) at any time within three (3) months after
the date of such termination of employment, but in no event after the expiration
of the Exercise Term.

            6.2   Termination of Employment Due to Death, Disability, or
                  Retirement.

                  If the Optionee's termination of employment is due to death,
Disability, or Retirement (termination of employment on or after age 65), or if
Optionee terminates employment after age 55, the following shall apply:

            (a)   Termination Due To Death.  In the event the Optionee dies
                  while actively employed, the Option shall become
                  immediately and fully exercisable, and shall remain
                  exercisable at any time prior to the expiration of the
                  lesser of one (1) year from the date of death or the
                  remaining Exercise Term, by (A) such person(s) that have
                  acquired the Optionee's rights under such Options by will
                  or by the laws of descent and distribution, or (B) if no
                  such person described in (A) exists, the Optionee's estate
                  or representative of the Optionee's estate.

            (b)   Termination by Disability. In the event the employment of the
                  Optionee is terminated by reason of Disability, the Option
                  shall become immediately and fully exercisable as of the date
                  the Committee determines the Optionee terminated for
                  Disability and shall remain exercisable at any time prior to
                  the expiration of the lesser of one (1) year from the date of
                  termination or the remaining Exercise Term.

            (c)   Termination by Retirement. In the event the employment of the
                  Optionee is terminated by reason of Retirement, the Option
                  shall continue to be exercisable (to the extent the Option was
                  vested and exercisable on the date of termination of
                  employment) and shall remain exercisable at any time prior to
                  the expiration of the lesser of five (5) years from the date
                  of termination or the remaining Exercise Term. In the event of
                  the Optionee's death after Retirement, the Option shall
                  continue to be exercisable in accordance with this



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                  subsection (c) as if the Optionee had lived and the Option
                  shall be exercisable by the persons described in (a) above.

            (d)   Termination After Attaining Age 55. If the Optionee terminates
                  employment (other than as a result of death or Disability)
                  after attaining age 55 but prior to age 65, unless the
                  Committee determines otherwise at the time of such
                  termination, the Option shall continue to be exercisable (to
                  the extent the Option was vested and exercisable on the date
                  of termination of employment) and shall remain exercisable at
                  any time prior to the expiration of the lesser of five (5)
                  years or the remaining Exercise Term. In the event of the
                  Optionee's death after Retirement, the Option shall continue
                  to be exercisable in accordance with this subsection (d) as if
                  the Optionee had lived and the Option shall be exercisable by
                  the persons described in (a) above.

      7.    Effect of Change in Control.

            7.1 Notwithstanding anything contained to the contrary in this
Agreement, in the event of a Change in Control, (i) the Option shall become
immediately and fully exercisable, and (ii) the Optionee will be permitted to
surrender for cancellation within sixty (60) days after such Change in Control,
the Option or any portion of the Option to the extent not yet exercised and the
Optionee shall be entitled to receive immediately a cash payment in an amount
equal to the excess, if any, of (A) the Fair Market Value, at the time of
surrender, of the Shares subject to the Option or portion of the Option
surrendered, over (B) the aggregate purchase price for such Shares under the
Option; provided, however, that if the Option was granted within six (6) months
prior to the Change in Control and the Optionee may be subject to liability
under Section 16(b) of the Exchange Act, the Optionee shall be entitled to
surrender the Option or any portion of the Option for cancellation during the
sixty (60) day period following the expiration of six (6) months from the Grant
Date and to receive the amount described above with respect to such surrender
for cancellation.

            7.2 If the employment of the Optionee is terminated within two (2)
years following a Change in Control, all vested Options shall continue to be
exercisable at any time within three (3) years after the date of such
termination of employment, but in no event after expiration of the Exercise
Term.

      8.    Nontransferability.

            The Option shall not be transferable other than by will or by the
laws of descent and distribution. During the lifetime of the Optionee, the
Option shall be exercisable only by the Optionee.


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      9.    No Right to Continued Employment.

            Nothing in this Agreement or the Plan shall be interpreted or
construed to confer upon the Optionee any right with respect to continuance of
employment by the Company or a Subsidiary, nor shall this Agreement or the Plan
interfere in any way with the right of the Company or a Subsidiary to terminate
the Optionee's employment at any time.

      10.   Adjustments.

            In the event of a Change in Capitalization, the Committee may make
appropriate adjustments to the number and class of Shares or other stock or
securities subject to the Option and the purchase price for such Shares or other
stock or securities. The Committee's adjustment shall be made in accordance with
the provisions of Section 11 of the Plan and shall be effective and final,
binding, and conclusive for all purposes of the Plan and this Agreement.

      11.   Terminating Events.

            Subject to Section 7 hereof, upon the effective date of (i) the
liquidation or dissolution of the Company or (ii) a merger or consolidation of
the Company (a "Transaction"), the Option shall continue in effect in accordance
with its terms and the Optionee shall be entitled to receive in respect of all
Shares subject to the Option, upon exercise of the Option, the same number and
kind of stock, securities, cash, property, or other consideration that each
holder of Shares was entitled to receive in the Transaction.

      12.   Withholding of Taxes.

            12.1 The Company shall have the right to deduct from any
distribution of cash to the Optionee an amount equal to the federal, state, and
local income taxes and other amounts as may be required by law to be withheld
(the "Withholding Taxes") with respect to the Option. If the Optionee is
entitled to receive Shares upon exercise of the Option, the Optionee shall pay
the Withholding Taxes (if any) to the Company in cash prior to the issuance of
such Shares. In satisfaction of the Withholding Taxes, the Optionee may make a
written election (the "Tax Election"), which may be accepted or rejected in the
discretion of the Committee, to have withheld a portion of the Shares issuable
to him or her upon exercise of the Option, having an aggregate Fair Market Value
equal to the withholding Taxes, provided that, if the Optionee may be subject to
liability under Section 16(b) of the Exchange Act, the election must comply with
the requirements applicable to Share transactions by such Optionees.12.2 If the
Optionee makes a disposition, within the meaning of Section 424(c) of the Code
and regulations promulgated thereunder, of any Share or Shares issued to him
pursuant to his exercise of the Option within the two-year period commencing on
the day after the Grant Date or within the one-year period commencing on the day
after the date of transfer of such Share or Shares to the Optionee


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pursuant to such exercise, the Optionee shall, within ten (10) days of such
disposition, notify the Company thereof, by delivery of written notice to the
Company at its principal executive office, and immediately deliver to the
Company the amount of Withholding Taxes.

      13.   Employee Bound by the Plan.

            The Optionee hereby acknowledges receipt of a copy of the Plan and
agrees to be bound by all the terms and provisions thereof.

      14.   Modification of Agreement.

            This Agreement may be modified, amended, suspended, or terminated,
and any terms or conditions may be waived, but only by a written instrument
executed by the parties hereto.

      15.   Severability.

            Should any provision of this Agreement be held by a court of
competent jurisdiction to be unenforceable or invalid for any reason, the
remaining provisions of this Agreement shall not be affected by such holding and
shall continue in full force in accordance with their terms.

      16.   Governing Law.

            The validity, interpretation, construction, and performance of this
Agreement shall be governed by the laws of the State of Delaware without giving
effect to the conflicts of laws principles thereof.

      17.   Successors in Interest.

            This Agreement shall inure to the benefit of and be binding upon
each successor corporation. This Agreement shall inure to the benefit of the
Optionee's legal representatives. All obligations imposed upon the Optionee and
all rights granted to the Company under this Agreement shall be final, binding,
and conclusive upon the Optionee's heirs, executors, Permitted Transferees,
administrators, and successors.

      18.   Resolution of Disputes.

            Any dispute or disagreement which may arise under, or as a result
of, or in any way relate to, the interpretation, construction, or application of
this Agreement shall be determined by the Committee. Any determination made
hereunder shall be final, binding, and conclusive on the Optionee and the
Company for all purposes.


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ATTEST:                             NATIONAL SERVICE INDUSTRIES, INC.




______________________________      By:_________________________________
           Secretary                    James S. Balloun
                                        Chairman, President, and
                                        Chief Executive Officer



                                    ______________________________
                                    Name of Optionee: ((Name))



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