The creation of the media-buying powerhouse -- 75% owned by Publicis and 25% by Cordiant Communications Group -- was the result of long-running negotiations between the two advertising giants over the future of Zenith. Publicis took over Saatchi & Saatchi's 50% of the media buyer when it bought the agency last summer.
The deal was finally announced in July and initially dubbed NewCo. It will have billings of over $17bn (£10.8bn) from 54 offices in 61 countries operating under the Optimedia and Zenith brands.
The brands will retain their own management, clients and offices, but with improved buying power, systems and software under the new structure.
Perriss will be joined by former Optimedia chairman Simon Lloyd, who becomes deputy chairman and CEO of Zenith Optimedia Group Europe and CEO of Optimedia Worldwide.
Former CEO of Zenith Media in the Americas, Rich Hamilton, takes up the post of CEO of the Zenith Optimedia Group the Americas; and Steve King, formerly chief executive of Zenith Media Europe, becomes CEO of Zenith Media Worldwide. King has also been appointed director of business and strategy development at the Zenith Optimedia Group.
John Taylor, Optimedia Worldwide's former director of operations, takes on the roles of director of strategic resources at the Zenith Optimedia Group and chief operating officer of Optimedia Worldwide.
Antony Young, who was CEO of Zenith Media Asia, becomes chief executive of the Zenith Optimedia Group Asia; and Adrian Sayliss becomes chief financial officer of the Zenith Optimedia Group.
Maurice Levy, president and chief executive of Publicis, takes on the additional responsibility of non-executive chairman of the Zenith Optimedia Group, while Cordiant CEO Michael Bungey adds the post of non-executive director of the Zenith Optimedia Group to his responsibilities.
Perriss said, "Our two shareholders were ad agency pioneers in creating standalone media agencies. As a result, we have two great global brands in Zenith and Optimedia with a superb client list and a great team. We have many ideas and plans on how we can create a new structure to benefit our clients, staff and shareholders."
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