Wunderman has shifted its Asia COO Steve Hsia to North America to take on a new role within the digital network.
Hsia has spent six years integrating Agenda across Wunderman in Asia, after acquiring the agency back in 2008.
No replacement has been announced and the agency said a hunt is now on.
"Steve has been a great partner and leader in developing our network in Greater China," Stephane Faggianelli, president of Wunderman Asia Pacific said.
"In North America, I have every confidence Steve will continue to be a positive force for change."