Chris C. O'Brien, former CIO for the city of Chicago, has been named a partner in the public-sector practice of IT consulting firm DiamondCluster International Inc. O'Brien has been a member of Mayor Richard M. Daley's cabinet for the past six years. In his new position, O'Brien will work primarily with city and state government clients.

Ingram named CIO at Argonaut Group

Robert C. Ingram III was named senior vice president and CIO, a new post, at Argonaut Group Inc., a San Antonio-based national insurance underwriter. He will report to CEO Mark E. Watson III. Ingram previously was a director at IBM and an associate partner at Andersen Consulting.

Vitesse chooses Ho, Browne for IT posts

Vitesse Semiconductor Corp., a Camarillo, Calif.-based supplier of Ethernet products to resellers, announced the appointments of Chi Fai Ho as chief technology officer and Paul Browne as vice president of engineering for its Ethernet products division. Ho, who will be responsible for advanced technology, most recently was vice president of engineering at Tidal Networks Inc. Prior to that, he was a senior director at Nokia Corp. Browne joined Vitesse from 3Com Corp., where he was most recently senior director of engineering.