The unusual step will see the J Walter Thompson name disappear from San Francisco.
JWT acquired Tonic 360, a San Francisco-based interactive agency, in October 2000. The merger creates an agency with £151m in billings and 100 employees. JWT & Tonic's clients include Sun Microsystems, Diageo/United Distillers & Vintners Wines and Northern California Ford Dealers.
The agency will be headed by Kevin Burke, formerly general manager of Tonic 360. He takes the role of managing partner and general manager. Iwan Thomis will become managing partner and director of strategic planning. He was formerly general manager of JWT San Francisco.
Bob Jeffrey, president of JWT North America, said, "The launch of JWT & Tonic represents much more than a combination of agencies. It marks a fundamental strategic reinvention of how we deliver communications on the West Coast."
JWT & Tonic will offer advertising, direct marketing and interactive communications.
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