In a business update email sent at midday New York time and obtained by The Drum, CEO Brian Lesser outlined GroupM's plans to transition to a 'single operating model' and indicated the forthcoming 'sunsetting' of 'agency-specific titles' across various markets.GroupM chief executive officer Brian Lesser has told staff there will be layoffs as the WPP media buying business embarks on a significant global restructuring to unify its operations.Following widespread reports today that GroupM will be rebranded as WPP Media, chief executive Brian Lesser shared an internal memo acknowledging the company will be "moving to a single operating model that brings the best of GroupM to our clients, with one voice in the market, and more opportunity for our people." Read more here