The restructure at Golin- Harris reflects 'the increasing influence of digital and social media', the company said.
The new model, called g4, is designed to better engage with audiences in an increasingly complex global environment.
Client teams now combine four areas of expertise - 'strategists' who will handle strategy; catalysts who will execute activity day-to-day; creators who will create content; and connectors to reach consumer and business audiences.
Each of the four communities will be headed by a leader, who will look to foster global collaboration, specialist training, best practice and thought leadership.
GolinHarris CEO and president Fred Cook said: 'Our US and UK offices have begun the transition to the new model, with the other offices doing so during the next six to 12 months. We expect the full agency to be operating under the new model by next year.'
He said the approach 'fuses insights, ideas and interaction into one integrated approach, communicating across all media channels, and engages audiences in the most unified and compelling way possible'.
The agency has also invested in The Bridge, networks of real-time multimedia technologies, which have begun operating in its London, New York and San Francisco offices.