
Sheehy transfers from SMG’s sister company Leo Burnett, where he was a member of the Leo Burnett Global Leadership Council and headed the agency's global Kellogg's account.
As president of global operations, Sheehy will lead SMG’s global operations teams and will "play a vital role in cultivating growth in SMG’s emerging markets, , chief of Starcom France and executive vice president of emerging markets," according to SMG.
Desmond said: "I have known John for over 20 years, and in that time I have always been inspired by his work ethic, ability to build winning teams and deliver world class business building ideas.
"We did not fill this role immediately, waiting instead for the right person with the right background. John is exactly the kind of executive who will do wonders connecting creative and media.
"I know he will play a crucial role in expanding our SMG footprint, ushering in new clients and evolving existing partnerships. He is the quintessential brand builder, client leader and creative trailblazer."
He will also be tasked with activating business in SMG core markets, working with local market leaders.
In addition, Sheehy will oversee several global accounts and will remain the executive head for SMG parent company Publicis Groupe on Kellogg's.
He said: "I have partnered my entire career with Starcom. I believe in their vision as the human experience company and will continue to integrate that practice throughout the internal and external infrastructures. The move is energizing and I look forward to being a part of their winning team."
Sheehy will join SMG’s executive management group and will lead SMG’s broader global management group in addition to his other responsibilities.
He replaces Andrew Swinand, who left SMG earlier this year, and will be based in the SMG offices in Chicago.