EXHIBIT 10.21
 
                         ROBERT HALF INTERNATIONAL INC.
                        SENIOR EXECUTIVE RETIREMENT PLAN
 
    1.    INTRODUCTION.    This  Plan was  adopted  by  the  Company  to provide
retirement benefits to those individuals, other than any individual holding  the
office  of  Chief  Executive  Officer  or  President,  who  participated  in the
Company's Deferred Compensation  Plan and,  with respect  to those  individuals,
this  Plan shall supersede the Deferred  Compensation Plan. The Administrator or
the Chief Executive Officer  may also select other  Participants to be  eligible
for benefits hereunder.
 
    2.    DEFINITIONS.   As  used in  this Plan,  the  following terms  have the
meanings set forth below:
 
    2.1 ADMINISTRATOR means the Compensation Committee of the Board.
 
    2.2 BOARD means the Board of Directors of the Company.
 
    2.3 CHANGE IN CONTROL means any of the following events:
 
        (a)   SCHEDULE 13D  OR 13G  FILING.   A  Schedule 13D  or 13G  is  filed
    pursuant  to the Exchange Act  indicating that any person  or group (as such
    terms are defined in  Section 13(d)(3) of the  Exchange Act) has become  the
    holder  of more than  forty percent (40%) of  the outstanding Voting Shares.
    For purposes of calculating the percentage of Voting Shares, such person  or
    group, BUT NO OTHER PERSON OR GROUP, shall be deemed the owner of any Voting
    Shares  which such person or group may acquire upon conversion of securities
    or upon the exercise of options, warrants or rights.
 
        (b)  CERTAIN CHANGES IN  DIRECTORATE.  As a  result of or in  connection
    with  any cash tender  offer, merger or other  business combination, sale of
    assets or contested election, or  combination of the foregoing, the  persons
    who  were directors  of the  Company just  prior to  such event  shall cease
    within one year to constitute a majority of the Board.
 
        (c)  GOING  PRIVATE.   The Company's stockholders  approve a  definitive
    agreement  providing for a transaction in which the Company will cease to be
    an independent publicly owned corporation.
 
        (d)  CERTAIN CORPORATE  TRANSACTIONS.  The  stockholders of the  Company
    approve  a definitive agreement (i) to merge or consolidate the Company with
    or into  another corporation  in  which the  holders  of the  Voting  Shares
    immediately  before  such  merger or  reorganization  will  not, immediately
    following such merger or reorganization, hold as a group on a fully  diluted
    basis  the ability  to elect  at least  a majority  of the  directors of the
    surviving corporation and  at least  a majority  in value  of the  surviving
    corporation's  outstanding equity securities,  or (ii) to  sell or otherwise
    dispose of all or substantially all of the assets of the Company.
 
        (e)  TENDER OR EXCHANGE  OFFER.  An Offer is  made by a person or  group
    (as such terms are defined in Section 13(d)(3) of the Exchange Act) and such
    Offer  has resulted in  such person or  group holding an  aggregate of forty
    percent (40%) or more of the outstanding Voting Shares. For purposes of this
    Section 2.3(e)  Voting  Shares  held  by  such  person  or  group  shall  be
    calculated in accordance with the last sentence of Section 2.3(a) hereof.
 
    2.4 COMPANY means Robert Half International Inc., a Delaware corporation.
 
    2.5 EXCHANGE ACT means the Securities Exchange Act of 1934, as amended.
 
    2.6  OFFER  means a  tender offer  or an  exchange offer  for shares  of the
Company's Stock.
 
    2.7 PARTICIPANT means any  elected executive officer  or any key  executive,
other  than  any individual  holding the  office of  Chief Executive  Officer or
President, approved  by the  Administrator or  the Chief  Executive Officer  for
participation  in  the  Plan.  The  benefits  of  individuals  (other  than  any
individual holding the office of Chief  Executive Officer or President) who  had
accounts (whether or
 
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not  vested) under the  Deferred Compensation Plan shall  be transferred to this
Plan, effective December 31, 1995, with  interest for 1995 credited at the  rate
and  as provided in Section 7  hereof instead of at the  rate and as provided in
the Deferred Compensation Plan. With respect to the year ended December 31, 1995
those individuals will thereafter be  Participants hereunder and will no  longer
participate in the Deferred Compensation Plan.
 
    2.8 PLAN means the Senior Executive Retirement Plan.
 
    2.9  VOTING SHARES means  the outstanding shares of  the Company entitled to
vote for the election of directors.
 
    3.  PURPOSE OF THE PLAN.  The purpose of the Plan is to attract, retain  and
reward  Participants by  providing them with  supplemental income  for use after
their retirement. The Plan is designed to qualify as an unfunded ERISA "top-hat"
plan for a  select group of  management or highly  compensated employees of  the
Company and its subsidiaries designated by the Administrator.
 
    4.   ADMINISTRATION.  The Administrator  shall have full power to interpret,
construe and administer the Plan, except as otherwise provided in the Plan.  The
expense of administering the Plan shall be borne by the Company and shall not be
charged against benefits payable hereunder.
 
    5.   DEFERRED COMPENSATION FORMULA.  Each Participant shall receive the base
salary and annual cash bonus payable  to that Participant for services  rendered
in  his capacity as an employee of the Company or a designated subsidiary during
the calendar year  of participation,  plus fifteen  percent (15%)  of such  base
salary  and annual  cash bonus as  deferred compensation pursuant  to this Plan,
provided he is employed  by the Company  on the last day  of such calendar  year
(December  31, 1995 for the first  year). A Participant's allocation of deferred
compensation hereunder  shall be  deemed to  have been  made, for  all  purposes
relating  to this Plan, as  of the first business day  of the year following the
year with respect to which the deferred compensation has been earned.
 
    The Administrator or the Chief Executive  Officer may at any time  designate
any  Participant as entitled to  receive a Change in  Control Allocation. Once a
Participant is  so  designated, such  designation  may not  be  rescinded.  With
respect  to any  Participant who  has been designated  as entitled  to receive a
Change in Control  Allocation, there  shall be allocated  to such  Participant's
account  promptly following a Change in Control (if such Participant is employed
by the Company  on the date  of the Change  in Control) an  amount equal to  the
product of (a) the number of whole years remaining until the Participant attains
age 62 and (b) the last annual allocation made under the Plan. After such Change
in Control Allocation has been made, each subsequent annual allocation under the
Plan  for such  Participant following  the Change in  Control and  prior to such
Participant's 62nd birthday  shall be  reduced by an  amount equal  to the  last
annual allocation made to such Participant prior to the Change in Control.
 
    6.    SEPARATE ACCOUNTS.   The  Administrator  shall maintain  an individual
account under the name of each  Participant entitled to allocations pursuant  to
the Plan. Each such account shall be adjusted to reflect any amounts transferred
from  the Deferred Compensation Plan,  deferred compensation credited hereunder,
interest  credited  on  such  amounts  and  any  distribution  of  such  amounts
hereunder.  The establishment  and maintenance  of a  separate account  for each
Participant shall not  be construed  as giving any  person any  interest in  any
assets  of the Company or any right  to payment other than as provided hereunder
or any right  to participate hereunder  or in future  years of employment.  Such
accounts  shall  be unfunded  and maintained  only for  bookkeeping convenience;
provided, however, the Company  may establish an  irrevocable grantor trust  and
contribute amounts to such trust to support its obligations hereunder.
 
    7.   INVESTMENT PERFORMANCE.  Each account shall be credited on the last day
of each calendar year  with interest on  the balance of such  account as of  the
first  day of the calendar year. Interest  credited for a calendar year shall be
at a  rate  equal to  one  hundred twenty-five  percent  (125%) of  the  Moody's
Corporate  bond Yield Average  reported in THE  WALL STREET JOURNAL  on the last
business day  of  the calendar  year  (or the  valuation  date selected  by  the
Administrator preceding a distribution).
 
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    8.    VESTING.    Each  Participant's  interest  under  the  Plan  shall  be
forfeitable upon such  Participant's termination of  employment for any  reason,
except  to the extent it becomes  vested hereunder. Each Participant's interest,
regardless of when  allocated, will  be deemed  unvested unless  and until  such
Participant  has  completed ten  years of  service with  the Company.  "Years of
Service" shall be  based on the  anniversary of the  later of the  Participant's
date of hire or his or her transfer to Company headquarters. At such time as the
Participant  has completed ten years service with the Company, the amount vested
at any given time shall be (a) 50%, if Participant is age 50 or younger, (b) the
sum of (i) 50%  and (ii) 4-1/6% times  the difference between Participant's  age
and 50, if Participant is between age 51 and age 62, or (c) 100%, if Participant
is  age 62 or older. In  the event of a Change  in Control, all amounts credited
under the  Plan to  each  affected Participant  shall  become fully  vested  and
nonforfeitable as a result of such event. Notwithstanding the foregoing, amounts
shall  vest hereunder in accordance with the terms of any severance agreement or
other written arrangement between the  Participant and the Company. In  addition
and  notwithstanding the foregoing,  the accounts transferred  to this Plan from
the Company's  Deferred  Compensation Plan,  including  any and  all  investment
performance  hereunder, shall continue  to vest under the  terms of the Deferred
Compensation Plan.
 
    9.  TIME  OF DISTRIBUTION.   No vested  amounts shall  be payable  hereunder
until the first to occur of the following events:
 
        (a)  The date  of the  Participant's complete  and total  disability, as
    determined by the Administrator  in its sole  discretion (without regard  to
    eligibility for benefits under any disability plan or program of the Company
    and/or its subsidiaries);
 
        (b) The Participant's death; or
 
        (c)  The date of  the Participant's separation  from employment with the
    Company and/or its subsidiaries for any reason.
 
    Notwithstanding the foregoing, distribution may occur at an earlier date  as
provided in Section 10 hereunder.
 
    All  vested amounts  will be  valued and paid  within 90  days following the
occurrence of any such event. If distribution occurs before the end of a year  a
Participant  shall  receive a  pro rata  amount  of deferred  compensation under
Section 5 hereof.
 
    10.  WITHDRAWALS.  The Administrator may direct payment of all or any vested
portion of amounts credited to the account of a Participant upon application  by
the  Participant. Any such application must show demonstrable financial need for
distribution in  order  to  meet  extraordinary  medical  or  medically  related
expenses,   substantial  costs  related  to   residential  requirements  of  the
Participant,  family  educational  expenses  in  an  amount  considered  by  the
Administrator  burdensome  in  relation  to  the  Participant's  other available
financial resources for meeting such expenses, extraordinary expenses related to
an unanticipated casualty,  accident or  other misfortune or  any other  similar
need approved by the Administrator.
 
    Any  such  distribution  shall  be  made  in  the  sole  discretion  of  the
Administrator.
 
    11.   METHOD OF  DISTRIBUTION.   Upon  termination  from the  Company,  each
Participant  shall receive a lump sum distribution of all amounts payable to the
Participant hereunder, unless prior to termination of employment the Participant
elects, and the Administrator consents to,  payment upon termination to be  made
in  the form of installments over a period of time approved by the Administrator
and not extending beyond the life expectancy of the Participant.
 
    12.  DEATH OF PLAN PARTICIPANT.   In the event that a Participant shall  die
at  any  time prior  to  complete distribution  of  all amounts  payable  to him
hereunder, the remaining  unpaid amounts  shall be  paid to  the beneficiary  or
beneficiaries  designated  by the  Participant, or  in the  absence of  any such
designation, to his estate in a lump sum distribution, unless the  Administrator
consents to installments.
 
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    13.   PAYMENT  IN THE  EVENT OF  DISABILITY.   If a  person entitled  to any
payment hereunder shall be under a legal disability, or in the sole judgment  of
the  Administrator shall otherwise  be unable to  apply such payment  to his own
interest and advantage, the Administrator in the exercise of its discretion  may
direct  the Company  to make  any such  payment in  any one  (1) or  more of the
following ways:
 
        (a) Directly to such person;
 
        (b) To his legal guardian or conservator; or
 
        (c) To his spouse or to any person charged with his support;
 
    to be  expended  for  the  benefit  of  Participant.  The  decision  of  the
    Administrator  shall in each case  be final and binding  upon all persons in
    interest. Any such payment shall completely discharge the obligations of the
    Administrator and Company with regard to such payment.
 
    14.  ASSIGNMENT.  No Participant or beneficiary of a Participant shall  have
any right to assign, pledge, hypothecate, anticipate or in any way create a lien
upon  any  amounts  payable hereunder.  No  amounts payable  hereunder  shall be
subject to assignment or transfer or otherwise be alienable, either by voluntary
or involuntary act or by operation of law, or subject to attachment,  execution,
garnishment,  sequestration or other seizure under any legal, equitable or other
process, or be liable in any way  for the debts or defaults of Participants  and
their  beneficiaries,  except  to the  extent  permitted by  applicable  law and
pursuant to the Administrator's  receipt and approval  of a "qualified  domestic
relations order."
 
    15.   WITHHOLDING.   Any  taxes required  to be  withheld from  deferrals or
payments to  Participants  hereunder  shall  be deducted  and  withheld  by  the
Company.
 
    16.   AMENDMENT AND  TERMINATION.  This Plan  may be amended  in whole or in
part by action of the Administrator and may be terminated at any time by  action
of  the Administrator; provided, however, that  no such amendment or termination
shall reduce  any  amount credited  hereunder  to  the extent  such  amount  was
credited  prior to the date of  amendment or termination; and provided, further,
that the duties and  liabilities of the members  of the Administrator  hereunder
shall not be increased without their consent.
 
    17.   RIGHTS OF PARTICIPANTS.  The Company's sole obligation to Participants
and their beneficiaries  shall be  to make  payment as  provided hereunder.  All
payments  shall  be  made  from  the  general  assets  of  the  Company,  and no
Participant shall have any right hereunder to any specific assets of the Company
or to be retained in the employment of the Company. All amounts of  compensation
allocated  under  this Plan,  any property  purchased  therewith and  all income
attributable thereto shall remain the property and rights of the Company subject
to the claims of the Company's general creditors.
 
    18.   BINDING PROVISIONS.   All  of the  provisions of  this Plan  shall  be
binding  upon all persons who  shall be entitled to  any benefits hereunder, and
their heirs, and personal representatives.
 
    19.  EFFECTIVE DATE.  This Plan shall be effective December 31, 1995.
 
    20.  GOVERNING LAW.  This Plan and all determinations made and actions taken
pursuant hereto shall, to the extent not preempted by ERISA, be governed by  the
law of the State of California and construed accordingly.
 
    21.    SEVERABILITY.    If  any  provision  of  this  Plan  is  held  to  be
unenforceable for  any reason,  it  shall be  adjusted  rather than  voided,  if
possible,  in order to achieve the intent of the parties to the extent possible.
In any  event, all  other provisions  of this  Plan shall  be deemed  valid  and
enforceable to the full extent possible.
 
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