Founded in 1985, Guye Benker's clients include Campari, UBS and Bohringer, and the agency had turnover of 2.8m Swiss francs (£1.24m) for the year ending June 2002. Terms of the deal were not disclosed.
WPP's other Swiss interests include public affairs and PR agencies, as well as advertising.
Yesterday, WPP announced two new members to its board: David Komansky, chairman of investment bank Merrill Lynch, and Howard Paster, the former chairman and chief executive officer of Hill & Knowlton. The company has since been criticised for the move, because of the links that both have with WPP, while the City expected both appointments to be independent.
Sir Martin Sorrell, chief executive of WPP, has dismissed the criticisms, telling the FT: "We have four executive directors and 10 non-executive directors, a chairman, a CEO and a senior non-executive director."
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