Wunderman has named former executive creative director at TBWA Hong Kong as chief creative officer of its flagship New York office.
Thessman joins Wunderman from Havas Worldwide where he served as executive creative director.
Thessman's appointment follows a significant new business haul at Wunderman and will lead accounts from United Airlines, Coca-Cola, E*TRADE and Isle of Capri.
The agency said he will work closely with Jamie Gallo, president of Wunderman New York and Lincoln Bjorkman, the agency's global chief creative officer.
"Sami is a proven leader able to combine technology, data and storytelling in order to help brands build innovative campaigns, with particular expertise in the technology and financial sectors," said Jamie Gallo, President of Wunderman New York.
Thessman moved to TBWA Hong Kong in 2013 and has worked with brands including Nissan, adidas, Apple, Lee Jeans, MasterCard, McDonald’s, Michelin and the NBA.