Terry Savage, the chief executive of the Cannes International Advertising Festival, said: "Media Lions is one of the most complex competitions to judge, therefore Mark's credentials and previous judging experience position him ideally for the role as Media Lions jury president."
Stewart joined Universal McCann in 1995 as media director, overseeing all New York accounts. In 1997, he was promoted to North American media director and more recently was promoted to chief strategy officer.
"I am extremely honoured and excited to accept this position, and the responsibility to build on the tremendous momentum of the Media Lions. In our current and evolving media landscape, promoting, developing, recognising and celebrating creativity and innovation in message distribution, as well as creative content, is critical to the future of client and our success," Stewart said.
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