Brian Lesser
Global CEO, WPP Media at wpp media
Global CEO of WPP Media, the agency holding company's media arm rebranded from GroupM in May 2025. A returning WPP executive — Lesser co-founded programmatic buyer Xaxis in 2011, ran GroupM North America, then left to lead AT&T's advertising business (later Xandr) and identity-data firm InfoSum before being recalled in 2024 to overhaul the world's largest media-buying group.
Lesser is one of the few agency-world executives whose career has bracketed the rise of programmatic, the platform-era ad-tech consolidation, and the current scramble around identity and AI. His return to WPP in 2024 — and the speed with which he moved to collapse the GroupM brand into a single WPP Media operating model the following May — has put him on the short list of executives reshaping how the largest media-buying organizations interface with platforms, measurement vendors, and the AI stack.