New GroupM North America CEO Talks WPP’s Plans for Its Largest Media Region

Tim Castree succeeds Brian Lesser, now with AT&T

The executive was formerly with Videology. GroupM
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WPP’s media network GroupM announced today that Tim Castree would be its new CEO for North America, filling a position left empty since Brian Lesser left approximately 16 months ago to help oversee AT&T’s ad platform.

Castree formerly served as global CEO of Wavemaker, the product of a 2017 merger between media agencies MEC and Maxus that sought to counter the turn toward commoditization in ad-buying services. Over the past year, he also assisted GroupM global CEO Kelly Clark in “reimagining the future” of an organization that provides a majority of WPP’s revenues in its largest global market—and that side project, Castree said, led Clark to assign him the North American leadership role.

The news comes one day after WPP CEO Mark Read presented investors and journalists with his new plan for WPP. Castree told Adweek GroupM’s strategy is in keeping with that “radical evolution.”

"We feel at this stage that further consolidation of [GroupM's] brands would inhibit our growth, not encourage it."
Tim Castree, North American CEO, GroupM

What we need to do is a microcosm of the larger story you heard from Mark [Read], which has lot to do with the simplification of our business for clients,” he said, describing his primary responsibility as “accelerating the modernization” of WPP’s media network.

While GroupM has been “reasonably healthy” in the U.S., many of the organization’s “incredible data assets” remain “a little locked away,” Castree added—and he plans to work with Clark to help make them a bigger part of the WPP business.

Castree will also help oversee the search for his replacement at Wavemaker. The agency struggled this year, posting negative growth primarily due to the losses of Campbell’s, Marriott and Barclays despite picking up business in the Adobe and Mondelez reviews and successfully defending Ikea. Castree also stated that Wavemaker won 67 percent of the reviews in which it participated and picked up approximately 300 new clients overall, including regional accounts.

I would also love to have two or three more significant global wins, because they tend to get all the headlines, but I’m looking to build a future-facing business that has many ways to grow,” he said, highlighting “revenue diversification” sources such as “precision marketing, analytics practices, [and] programmatic models.”

Contrary to rumors that Wavemaker would be merging with another GroupM agency, Castree said all of the network’s properties will retain their individual brands, even as Mark Read focuses more of WPP’s resources on creative services.

“We feel at this stage that further consolidation of these brands would inhibit our growth, not encourage it,” the incoming executive said.

@PatrickCoffee Patrick Coffee is a senior editor for Adweek.