The agency will lead creative, experience and strategy for Hyatt’s loyalty program.
Grivas will replace Matt Sallis, who has resigned after running the market remotely from Canada for the past year.
Chan leaves her PHD post after just six months to rejoin Dentsu International.
The Wavemaker vet will lead performance and predictive intelligence globally.
The holding company will take over media duties for the global automaker in the US, Canada and Europe.
EXCLUSIVE: Agency has hired iProspect's Mark Fagan to lead its ambitious Asia-Pacific plans as it targets seven offices within four years.
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