(FORTUNE Small Business Magazine) -- Steve Singh, CEO OF Concur Technologies (No. 51), used to file travel and expense reports just like everyone else: late. A former software exec, Singh found the task tedious - everything had to be done by hand, data entered by the accounting department, checks cut weeks later.

In Singh's case, procrastination was the mother of invention: Why not automate expense reports? In 1993 he co-founded Concur (Charts) (concur.com) in Redmond, Wash., with his brother, Raj, and a partner. Since then its software has become the market leader in online expense filing and reporting, with clients including Dell (Charts), Airbus, and some 1,500 small firms.

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Singh, 45, is now moving to expand. In early 2006, Concur acquired Outtask, makers of an application to manage corporate travel. Singh hopes to offer clients a way to book all their work travel, expense it, and analyze the data with just a few mouse clicks. It's an acquisition he and his partners hope will be on the money.

Next FSB 100 company: No. 78: Ambassadors Group

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