ADMINISTAFF ANNOUNCES EXPANSION OF SHARE REPURCHASE PROGRAM

HOUSTON, TX – May 7, 1999 – Administaff, Inc. (NYSE: ASF), a leading Professional Employer Organization (PEO), today announced that the Board of Directors has authorized the repurchase of up to one million additional shares of the company’s outstanding common stock. The purchases are to be made from time to time in the open market or directly from shareholders at prevailing market prices based upon market conditions and other factors. This authorization is in addition to a one million share repurchase program announced in January of this year. Of the initial one million shares authorized, the company has repurchased 875,000 shares. The company currently has 13,645,691 shares outstanding.

"The expansion of our share repurchase program reflects our continued confidence in Administaff’s prospects," said Richard G. Rawson, executive vice president and chief financial officer. "Buying back shares which we believe to be significantly undervalued will also assist us in managing any dilutive effect experienced as a result of adding additional shares to our incentive plan." Stockholders at the company’s annual meeting held May 4, 1999, approved an amendment authorizing the addition of 600,000 shares to the company’s employee stock option plan.

Administaff provides small and medium-sized businesses with a comprehensive Personnel Management System that includes benefits and payroll administration, medical and workers’ compensation insurance programs, personnel records management, employer liability management, employee recruiting and selection, performance management, and training and development services. The company currently has 25 offices in 15 major markets and serves clients and worksite employees throughout the United States. For additional information, visit the company’s web site at www.administaff.com.

(NOTE: The statements contained in this press release that are not historical facts are forward-looking statements that involve a number of risks and uncertainties. Therefore, the actual results of future events described in such forward-looking statements could differ materially from those stated in such forward-looking statements. Among the factors that could cause actual results to differ materially are: (i) regulatory and tax developments; (ii) changes in the company's direct costs and operating expenses; (iii) the effectiveness of the company's sales and marketing efforts, including its marketing agreement with American Express, American Express' ability to set qualified appointments and the company's ability to convert those appointments into sales; (iv) the estimated costs and effectiveness of capital projects and investments in technology and infrastructure; (v) changes in the competitive environment in the PEO industry; and (vi) the effectiveness and estimated costs of the company's Year 2000 conversion and contingency plans. These factors are described in further detail in the company's filings with the Securities and Exchange Commission.)