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                                                                    EXHIBIT 10.2

                                Administaff, Inc.
                          19001 Crescent Springs Drive
                               Kingwood, TX 77339


February 16, 2001

American Express Foundation
American Express Tower
World Financial Center
200 Vesey Street
New York, New York 10285

Dear Sirs:

This letter sets forth the parties' agreement with respect to the purchase by
Administaff, Inc. ("ASF") from the American Express Foundation ("Foundation") of
up to 525,000 shares of ASF common stock, par value $0.01 per share (the
"Shares").

The parties agree as follows:

1.       ASF agrees to purchase up to 525,000 Shares from the Foundation at a
         purchase price per share equal to ninety-nine percent (99%) of the
         average of the closing sales prices of a Share as reported on the New
         York Stock Exchange composite transactions tape and reflected in the
         three star New York City edition of the Wall Street Journal over a
         twenty (20) trading-day period, of which the first ten trading days end
         on February 16, 2001 and the second ten trading days commence on the
         day that ASF releases its earnings report for the fourth quarter of
         2000.

2.       ASF's obligation to purchase the Shares is conditional upon (a)
         American Express Travel Related Services Company, Inc. ("TRS") first
         having exercised its warrant to purchase 800,000 shares of ASF common
         stock (the "Warrant Shares") at an exercise price of $20 per Warrant
         Share (subject to adjustment in accordance with the terms of the
         warrant) on or before March 10, 2001, the expiration date of the
         warrant; (b) the per share purchase price calculated as set forth in
         (1) above not exceeding $30; and (c) the Foundation notifying ASF that
         it is exercising its right to sell Shares under this Agreement not
         later than 5:00 p.m. on March 12, 2001.

3.       It is understood and agreed by the parties that TRS is not obligated to
         exercise the warrant, provided that if TRS does exercise the warrant
         and thereafter the Foundation desires to sell up to 575,000 Shares on
         or before March 12, 2001, the Foundation shall sell such Shares first
         pursuant to this Agreement.

4.       The closing of the sale and purchase will take place on March 12, 2001
         or such other day determined by the Foundation and ASF. At the closing,
         ASF will pay to the Foundation the aggregate purchase price for the
         Shares by wire transfer of immediately


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         available funds, and Foundation will deliver to ASF certificates
         representing the Shares, duly endorsed for transfer.

5.       The Foundation will pay all stamp, transfer and similar taxes and all
         federal and state income taxes in connection with the Foundation's sale
         of the Shares.

6.       The Shares Foundation intends to sell are those common shares
         originally purchased by TRS from ASF in March 1998 and contributed by
         TRS to the Foundation. The parties shall execute any additional
         documents, if any, reasonably required for the Foundation to adequately
         identify the Shares sold by it hereunder as being the shares originally
         purchased by TRS from ASF in March 1998.

7.       ASF will prepare a press release pursuant to which it will announce
         this agreement. Such release shall require the prior approval of the
         Foundation, such approval not to be unreasonably withheld.


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8.       This letter agreement shall be governed by the laws of the State of New
         York, without reference to conflict of laws rules.

                               ADMINISTAFF, INC.


                               By: /s/ Richard G. Rawson
                                  ----------------------------------------------
                               Richard G. Rawson
                               Executive Vice President of Administration,
                               Chief Financial Officer and Treasurer


AGREED:

AMERICAN EXPRESS FOUNDATION


By: /s/ David I. Yowan
   ----------------------------------
Name:      David I. Yowan
Title:     Treasurer