Sintras had also recently taken on the task of leading the network's human experience strategy global team.
He will be joining Mediabrands in a newly created role: global business development and product innovation. Sintras will report directly to Henry Tajer, newly appointed global CEO of Mediabrands.
"It is an opportunity that is a logical next step for my career," commented Sintras.
SMG has decided not to fill Sintras' chairman role in Australia, while the global role will be taken on by US-based Kathy Kline, a current member of SMG’s Global Product Committee.
“It’s been a long and truly amazing journey with SMG in Australia and globally," said Sintras. "I am enormously proud of the many milestones we have achieved together and I know that I leave the Australian business under the capable leadership of Chris Nolan [CEO of SMG Australia] and his executive team."
“[Sintras] has made huge difference to my career and personally I am proud to have had the opportunity to work with John and count him as a colleague and friend," said Nolan. "We all wish him well with his new adventure.”
Nolan will continue reporting into SMG President, Asia-Pacific, Mike Amour.
Sintras’s departure date from SMG is yet to be announced.
Updated on August 6 to include details of Sintras' new role with Mediabrands