<PAGE>
                                                            Exhibit 10(iii)A(24)

                        INCENTIVE STOCK OPTION AGREEMENT




         THIS AGREEMENT, made as of the 23rd day of September 1997 (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 $44.3125 per Share.

         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
<PAGE>

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.

         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 below, the Optionee's right to exercise any then
outstanding Options (whether or not
<PAGE>

vested) shall terminate immediately upon Termination of employment.

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

                  If the Optionee's Termination of employment is due to death,
Disability or Retirement (termination of employment on or after age 65), or
within two (2) years following a Change in Control, 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) years
after the date of such Termination of employment, but in no event after the
expiration of the Exercise Term. In the event of the Optionee's death, the
Option shall be exercisable, to the extent provided in the Plan and this
Agreement by (A) such persons that have acquired Optionee's rights by will or
the laws of descent and distribution, or (B) if no such person in (A) exists, by
the Optionee's estate or a representative of the Optionee's estate.

         7.       Effect of Change in Control.

                  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.

         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.

         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.

<PAGE>


         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 l6(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 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.

<PAGE>


         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.

         19.      Shareholder Approval.

                  The effectiveness of this Agreement and of the grant of the
Option pursuant hereto is subject to the approval of the Plan by the
stockholders of the Company in accordance with the terms of the Plan.

<PAGE>


ATTEST:                                     NATIONAL SERVICE INDUSTRIES, INC.




___________________________________         By:________________________________
          Secretary                            James S. Balloun
                                               Chairman, President, and
                                               Chief Executive Officer




                                            ___________________________________
                                            Name of Optionee: ((Name))