OneMind provides business software to manage employees' expense reports, and serves more than 5,000 companies worldwide. It is based in Irvine CA.

OneMind's management and staff will remain, and the company will continue to operate as ExpensAble.

Terms of the transaction were not announced. Administaff said acquisition costs and first year operations won't be material to 2010 results.

"This acquisition advances our corporate strategy of developing profitable adjacent business units with recurring revenue streams, strong growth potential and substantial cross-selling opportunities to grow our core PEO business," said Administaff Chairman and CEO Paul Sarvadi.

The deal was announced today.