Tim Castree, the managing director of independent video ad platform Videology in North America, was named to succeed Mr. Courtier at the helm of MEC Global in January.
In his new role, Mr. Castree will be responsible for MEC's 5,000 staffers worldwide who work on client business across 93 countries. He will be based in New York and report to GroupM Global CEO Kelly Clark, who returned to the WPP media investment company in September after having served as CEO of GroupM in North America from 2012 to 2015.
Before Videology, Mr. Castree was U.S. chief operating officer for Publicis Groupe's Mediavest, working on brands such as American Honda Motor Company, Mondelez, Coca-Cola, Microsoft and Sprint. Prior posts include global managing director for Stacom Mediavest, where he oversaw global P&G business across 70 countries.
Mr. Courtier, whose tenure with WPP goes back nearly 20 years, will continue continue working with the holding company through June.