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                                                             Exhibit 10(iii)A(5)


                        INCENTIVE STOCK OPTION AGREEMENT
              FOR EXECUTIVE OFFICERS AND OPERATING UNIT PRESIDENTS




         THIS AGREEMENT, made as of the 15th day of May, 2000(the "Grant Date"),
between   National   Service   Industries,   Inc.,   a   Delaware    corporation
(the "Company"), and Joseph G. Parham, Jr. (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 the  Company or one of its
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 10,000
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 $23.125 per Share.



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                                                             Exhibit 10(iii)A(5)


         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, 25% of the total number of Shares covered by the Option after
the  expiration of one (1) year from the Grant Date and an additional 25% of the
total number of Shares covered by the Option on each of the second,  third,  and
fourth  anniversaries  of the Grant Date.  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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                                                             Exhibit 10(iii)A(5)

         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  Sections  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  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 vest in
                           accordance  with the  original  schedule  (just as if
                           the Optionee had remained  employed) 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 vest and  be exercisable in
                           accordance  with  this  subsection  (c)   as  if  the


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                                                             Exhibit 10(iii)A(5)

                           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  vest  in  accordance  with   the
                           original  schedule  (just as  if  the  Optionee   had
                           remained employed)  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 vest and 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 thereof  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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                                                             Exhibit 10(iii)A(5)


         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 and Notice of Disposition.

                  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


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                                                             Exhibit 10(iii)A(5)

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.

         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,  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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                                                             Exhibit 10(iii)A(5)


ATTEST:                                   NATIONAL SERVICE INDUSTRIES, INC.



/s/ Helen Haines                             By: /s/ James S. Balloun
Secretary                                    James S. Balloun
                                             Chairman, President, and
                                             Chief Executive Officer




                                             /s/ Joseph G. Parham, Jr.
                                             Name of Optionee:
                                             Joseph G. Parham, Jr.