Brian Lesser is an American businessman currently serving as Chief Executive Officer at WPP Media, a role he assumed in 2024. His career is marked by leadership positions across major advertising and ad-tech companies, including previous CEO roles at Xandr, an AT&T subsidiary, and GroupM, a WPP company.
Lesser's tenure at GroupM began in 2011 when he founded Xaxis as a subsidiary. He later became CEO of GroupM in November 2015, overseeing six media agencies until October 2017.