Scott will join Droga5’s London office in October as chief executive and will report to the agency's global chief executive, Sarah Thompson.
In the interim, Droga5 Europe has been run by Nick Simons, who relocated from the agency’s New York office to become managing director in London. Simons will stay in London as managing director and report to Scott.
Scott joins Droga5 from Grey, where he has been the managing director since 2012. Before Grey Scott was a managing partner at Bartle Bogle Hegarty, where he worked for 13 years. Natalie Graeme, who has been the managing director at Grey London since May, will take on Scott's responsibilities.
Droga, the creative chairman of Droga5, said: "Bill is everything we were looking for in a CEO and more. A natural leader, blessed with the humility, class and inspiring ambitions that make him the perfect fit for this company."
Droga5’s London office is also looking for a new executive creative director, after Nik Studzinski left for Karmarama in May.
Duncan Marshall, a partner and executive creative director at Droga5’s New York office has temporarily relocated to London to run the creative department until the new hire arrives.