Jerry Buhlmann, CEO of Dentsu Aegis, joins the Guardian's Mark Sweney in the Speakers' Lounge at the Cannes Lions festival
Sir Martin Sorrell hits out at 'clunky' rival Publicis Omnicom as advertising group reports strong 5% revenue growth for July. By Mark Sweney
WPP chief executive Martin Sorrell would be unseated as advertising's top dog as investors sense further consolidation