Mescall, who has been ECD of McCann Australia since October 2011 will relocate to New York in the coming months to take up his new role.
He will join fellow global ECDs James Dawson-Hollis and Bill Wright. The move is part of McCann’s global creative chairman, Rob Reilly’s, attempt to strengthen the agency’s creative leadership team.
Reilly said: "John’s all talent and no ego and he has helped lead McCann Australia to become one of the best agencies in the world. John now has the opportunity to magnify what he does on a global stage. I am certain that John’s reputation for delivering stellar work will be a magnet for recruiting the best and brightest to McCann."
McCann said its Australian branch had become one of the country’s "most dynamic and most awarded agencies" under Mescall’s leadership.
Prior to working at McCann, Mescall was partner and ECD at SMART, an independent agency in Australia which was bought by McCann Worldgroup in 2011.
Mescall boasts more than 30 Cannes Lions during his career so far, including five Grand Prix for Metro Trains 'dumb ways to die' and another Grand Prix for creative effectiveness for the train operator V/Line.
His other awards include Black and Yellow Pencils at the respected D&AD awards and his work has also been featured in TED’s 'Ads Worth Spreading' initiative.
Mescall said: "It’s a seriously exciting time at McCann. The opportunity to work closely with Rob was just too big not to take, and we're very aligned on the kind of work we seek to do.
"He has a very ambitious agenda for the network and wants creativity to permeate everything we do. The move allows me to leverage my experience, and I look forward to playing a bigger role in our collective future."