He will take over the CEO role at Initiative from Lou Schultz, who announced his retirement from the Interpublic Group of Companies-owned Initiative in January.
Gerster is to be replaced at MediaCom, owned by Grey Global, by Alexander Schmidt-Vogel, who is currently chief operating officer. At the same time, MediaCom has promoted Dene Callas and Jon Mandel as co-CEOs of MediaCom's US operations. They were previously co-managing directors.
Schmidt-Vogel joined Grey Dusseldorf in 1976 and was made CEO of MediaCom Germany in 1988. He was appointed to his current role in May 2001.
Edward Meyer, chairman, president and CEO of Grey, said: "These promotions are in recognition of the outstanding job Jon and Dene have been doing over the past several years as co-managing directors of MediaCom in the US."
Initiative Media operates 85 offices in 45 countries, with estimated global billings of $22.7bn (£15.9bn) in 2001. MediaCom's 67 offices generate over $11bn in billings.
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