2ND AMEND.TO AMENDED EMPLOYEE STOCK PURCHASE PLAN

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                                                                   EXHIBIT 10.12

                      SECOND AMENDMENT TO ADMINISTAFF, INC.

                          EMPLOYEE STOCK PURCHASE PLAN

         The Administaff, Inc. Employee Stock Purchase Plan, as amended and

restated effective April 1, 2002 ("Plan") shall be, and hereby is, amended in

the following respects:

                                       I.

         Effective August 15, 2003, Section 8(a) of the Plan is amended in its

entirety to provide as follows:

                  "8.       Purchase of Shares.

                  (a)       Following the end of each Purchase Period, the

         Participants' Accounts shall be applied automatically by the

         Recordkeeper to purchase the maximum number of shares of Common Stock

         that may be purchased with the accumulated payroll deduction and

         dividends,