First-quarter revenue at On Assignment Inc. (NASD: ASGN) rose 24.3% to $152.4 million, above its guidance. The Calabasas CA-based staffing firm reported revenue of $122.6 million in the first quarter of last year.

Net income increased 163.8% to $2.4 million in the first quarter from $911,000 in the first quarter of 2007. Gross margin improved to 31.1% from 30.5%.

Senior VP and CFO Jim Brill said most of the increase in gross margin came from the company's higher margin information technology and engineering business. On Assignment acquired IT and engineering staffing firm Oxford Global Resources Inc. in February 2007.

The company's revenue in the IT and engineering segment rose 80.3% to $54.7 million. On Assignment posted IT and engineering revenue $30.3 million in the first quarter of 2007, which had only two months of revenue due to its acquisition of Oxford.

In other segments, On Assignment's first-quarter life sciences revenue rose 2.9% to $32.6 million; healthcare revenue rose 4.4% to $44.5 million; and physician staffing revenue rose 14.5% to $20.6 million.

The company estimated second-quarter revenue of $153 million to $156 million, up 6.4% to 8.4% over the second quarter of 2007, and net income of $4.0 million to $5.1 million, up 36.1% to 73.6% over the same period in the previous year.

On Assignment Inc. (NASD: ASGN)
For the first quarter ended March 31, 2008, compared with the same period in 2007.
Revenue $152.4 million, +24.3%
Net income: $2.4 million, +163.8%