Second-quarter revenue rose 8.5% at On Assignment Inc. (NASD: ASGN). The Calabasas CA-based firm posted 20.4% year-over-year growth in its physician staffing business and 15.7% in its information technology and engineering staffing business.

Overall, On Assignment posted second-quarter revenue of $156.1 million, compared with $143.9 million in the same period last year.

Gross margin improved to 32.5% from 32.1%. Net income increased 107.4% to $6.1 million from $2.9 million in the second quarter of 2007. The last quarter included a non-cash gain of $1.1 million related to an interest rate swap.

The company reported physician staffing revenue of $21.8 million, up from $18.1 million in the same period last year. IT and engineering staffing revenue rose to $56.3 million year-over-year from $48.7 million. On Assignment acquired IT and engineering staffing firm Oxford Global Resources Inc. and physician staffing firm Vista Staffing Solutions Inc. in early 2007.

The company's healthcare staffing revenue rose 5.0% to $45.8 million. Second-quarter revenue in its life sciences staffing business fell 3.8% year-over-year to $32.1 million.

On Assignment estimated third-quarter revenue of $156.5 million to $160.0 million, an increase of 8.8% to 11.2% over the same period in the previous year.

On Assignment Inc. (NASD: ASGN)
For the second quarter ended June 30, 2008.
Revenue: $156.1 million, +8.5%
Net income: $6.1 million, +107.4%