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                                                             Exhibit 10(iii)A(b)



                                  May 14, 1996




J. Robert Hipps
5021 Northside Drive, N.W.
Atlanta, Georgia  30327-4421


Dear Bob:

This letter will  confirm our  agreement  with  respect to your  termination  of
employment with National Service Industries, Inc. ("NSI").

     1. Effective Date. Your  termination of employment will be effective on May
31, 1996 (the  "Effective  Date").  Our expectation is that you will continue to
work until the Effective Date, unless I advise you otherwise,  in which case you
will be placed on a paid leave of absence until the Effective Date.

     2.  Severance  Pay. NSI will pay you, as severance  pay, an amount equal to
your  salary  at the  current  monthly  rate  for a  twelve  (12)  month  period
commencing on June 1, 1996 and  continuing  until May 31, 1997.  Payment of your
severance pay will be made on a semi-monthly basis. You will also be entitled to
a pro rata share of your bonus for fiscal year 1996 payable in September, 1996.

     3.  Additional  Benefits.  If  you  elect  COBRA  coverage  following  your
termination  of  employment,  you will continue to pay the portion of the health
insurance  premium  cost which you  currently  pay to NSI,  and NSI will pay the
remaining amount of your monthly premiums for COBRA coverage (including coverage
for your wife) until the sooner of (a) your  qualification  under a medical plan
offered by your employer,  or (b) May 31, 1997. NSI will amend your Stock Option
Agreements  in two  respects:  (1) stock  options that would  otherwise  vest in
September,  1996  will  vest on or  before  May 31,  1996;  and (2) the time for
exercising  all vested stock  options will be extended  until May 31, 1997.  You
will receive a pension annuity  commencing on June 1, 1996 or on such other date
as you elect prior to your 65th birthday. The amount of the pension annuity will
be determined  based upon the pension  annuity you would have received under the
Supplemental  Retirement  Plan for Executives of NSI (effective as of January 1,
1994) if you had had four  additional  years of credit and had been eligible for
early retirement under the Supplemental Retirement Plan for Executives of NSI on
the Effective Date. An
     

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                                                             Exhibit 10(iii)A(b)

Page 2
J.R. Hipps
May 14, 1996



appendix to such plan will be added in the form attached to this letter. In lieu
of the  annuity,  you may elect to receive a lump sum  equivalent  as of May 31,
1996 (calculated  using a discount rate of 8%). You will also receive a lump sum
payment on June 15,  1996 in the amount of  $41,877  to  compensate  you for the
difference  between the  Interest  Earnings  Rate and the  Termination  Interest
Earnings Rate under the Senior  Management  Benefit  Plan,  assuming an Interest
Earnings Rate of eleven percent (11%) going forward and a discount rate of eight
percent (8%), and for the unvested portion of your 40l(k) plan account. Further,
we confirm that the Company  Contribution  Amount for you under the  Executives'
Deferred Compensaton Plan will vest on the Effective Date. In addition, NSI will
pay for  out-placement  services  in  accordance  with the  executive  placement
program offered by Right Associates.

     4. Other Terms of Payment. You acknowledge that the foregoing severance pay
and  benefits  exceed  those  which  you  would  otherwise   receive  upon  your
termination  of  employment.  Your severance pay and benefits will be subject to
appropriate tax  withholdings and will satisfy all sums which might otherwise be
due you from NSI, including,  without limitation,  vacation pay and bonuses, but
excluding any payments due you under the Executive  Deferred  Compensation  Plan
for Senior Officers,  the Senior Management  Benefit Plan, the Executive Savings
Plan, NSI's Pension Plan C, the  Supplemental  Retirement Plan for Executives of
NSI  (effective as of January 1, 1994),  and NSI's 40l(k) Plan,  which  payments
will be made in  accordance  with  the  terms  of such  plans.  You  will not be
eligible to participate in any employee benefit plans following your termination
on the Effective  Date,  except as provided  above and as provided for under the
Consolidated Omnibus Budget Reconciliation Act of 1985 ("COBRA"), as amended.

     5.  Conditions  to  Payment.  You  understand  that the  severance  pay and
benefits  provided for hereunder are  conditioned  upon (a) your not disparaging
NSI or any  officer,  director or employee of NSI in any material  respect;  (b)
your not  disclosing  to any person or using for your own  benefit,  directly or
indirectly,  any  trade  secrets  or  confidential  information  of NSI,  unless
directed to do so by court order;  (c) your not  soliciting,  either directly or
indirectly,  any current employees of NSI to terminate their employment with NSI
and become employed by you or any person or entity with whom you are associated;
(d) your  compliance  with the  provisions  of  paragraph  6 below,  and (e) the
approval of the  Executive  Resource  and  Nominating  Committee of the Board of
Directors  of NSI.  In the event you  violate  any of the  foregoing  conditions
(other than the condition set forth in  subparagraph  (d) above) within a period
of five (5) years after the date hereof,  NSI may suspend all further  severance
pay and benefits provided hereunder.  In the event you violate the condition set
forth in  subparagraph  (d)  above at any time  prior to the  expiration  of the
applicable statutes of limitations, NSI may suspend all further



                                                                         Page 15
                                                             Exhibit 10(iii)A(b)

Page 3
J.R. Hipps
May 14, 1996



severance pay and benefits provided hereunder.  In addition, NSI may at any time
pursue any other remedies to which it may be entitled at law or in equity.

     6. Release.  In consideration of enhanced  severance pay and benefits,  and
subject to the  fulfillment  of the  condition  provided  in  subparagraph  5(e)
hereof, as described above, you hereby release and forever discharge NSI and its
divisions,  subsidiaries,  and  affiliates  and their  respective  shareholders,
officers,  directors,  employees,  agents or others acting on their behalf,  and
each of them, from any and all claims,  losses or expenses (including attorneys'
fees)  which you now have or have had or may  later  claim to have had as of the
date  hereof  against  them  arising  out of  your  employment  with  NSI or the
termination  of your  employment.  You  understand and agree that as a result of
this release and discharge, you will not, for example, be entitled to pursue any
claims  arising out of any alleged  violation of your rights  while  employed by
NSI,  including,  but not limited to, (a) claims for back pay,  reinstatement or
recovery of any losses or  compensatory,  punitive,  or other  damages to you or
your property resulting from any alleged violation of state or federal law, such
as (but not limited to),  claims arising under Title VII of the Civil Rights Act
of 1964, 42 U.S.C. SS 2000e, et. seq. (prohibiting  discrimination on account of
race,  color,  sex,  national  origin or religion);  the Age  Discrimination  in
Employment Act of 1967, 29 U.S.C. SS 621, et. seq.  (prohibiting  discrimination
on account of age);  the Americans  with  Disabilities  Act of 1990, 42 U.S.C SS
12101,  et. seq.  (prohibiting  discrimination  on account of  disability);  the
Family and Medical  Leave Act of 1993  (relating to leaves of absence for family
and medical  reasons);  and any similar  federal or state law claim  relating to
your employment;  and (b) claims resulting or arising from or in connection with
any alleged tortious conduct or other wrongdoing by NSI.

     7.  Acceptance  Period.  You have a period of twenty-one (21) days from the
date hereof to consider  whether or not you will accept the terms and conditions
set forth herein. You are advised to consult with an attorney and anyone else of
your  choosing  to obtain  advice  and  information  concerning  such  terms and
conditions.  In order to receive  the  severance  pay and  benefits,  it will be
necessary for you to accept such terms and  conditions by signing both copies of
this letter  agreement and returning one (1) copy to me within  twenty-one  (21)
days from the date hereof.

     8.  Revocation  Period.  You  understand  that  for a  period  of up to and
including seven (7) days after the date you sign this letter agreement,  you may
revoke it entirely.  No rights or obligations  contained in this agreement shall
become  enforceable  before the end of this seven (7) day revocation  period. If
you decide to revoke this letter agreement,  you will deliver a signed notice of
revocation  to me on or  before  the end of this  seven  (7)  day  period.  Upon
delivery  of a timely  notice of  revocation,  this  letter  agreement  shall be
canceled and void, and neither party to this letter agreement shall have


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                                                             Exhibit 10(iii)A(b)

Page 4
J.R. Hipps
May 14, 1996



any rights or obligations arising under it.

     9.  Nondisclosure  Covenant.  You  agree  to hold  this  agreement  and the
contents  hereof in strict  confidence  and not to disclose such contents to any
third party,  other than your family  members and financial and legal  advisors,
without the prior written approval of NSI.

     10. Nondisparagement by NSI. NSI agrees to take appropriate steps to ensure
that the officers of NSI will not disparage you.

     11.  Miscellaneous.  This letter agreement constitutes the entire agreement
of the parties and  supersedes  any prior  agreements,  whether oral or written,
between the parties,  including  any prior  employment  agreements.  This letter
agreement  shall be binding upon and inure to the benefit of the  successors and
assigns  of  NSI  and  your  heirs,   administrators,   executors  and  personal
representatives.  If any provision of this letter  agreement is determined to be
unenforceable by a court of appropriate  jurisdiction,  the remaining provisions
of this letter agreement will continue in effect at the discretion of NSI.

     12. Statement of Understanding. YOU STATE THAT YOU HAVE CAREFULLY READ THIS
LETTER  AGREEMENT,  UNDERSTAND ITS MEANING AND INTENT,  AND VOLUNTARILY AGREE TO
ABIDE BY ITS TERMS. YOU FURTHER STATE THAT THE ONLY PROMISES MADE TO YOU TO SIGN
THIS LETTER AGREEMENT ARE SET FORTH HEREIN.

                                                     Sincerely,


                                                     /s/ James S. Balloun
                                                     James S. Balloun


AGREED TO AND ACCEPTED THIS
17th DAY OF       May   , 1996.



/s/ J. Robert Hipps
J. Robert Hipps