GroupM

GroupM, a media investment management company, is based in New York City, USA, and consolidates various media agencies to handle media buying and planning for clients globally. As the world's largest media investment group as of 2023, GroupM leverages its scale for trading, innovation, and communication services, operating a 700,000-square-foot headquarters. The organization integrates operations from agencies such as Mindshare, Mediacom, Maxus, MEC, and Xaxis, providing competitive advantages to its diverse client base. Brian Lesser was appointed global CEO in 2024, overseeing its extensive global presence, which includes over 220 employees in its Vietnam office alone. GroupM was established in 2003 by WPP plc through the merger of Mediaedge: CIA and Mindshare Worldwide, and is slated to be renamed WPP Media on May 27, 2025.