Omnicom Media Group has appointed Guy Marks, its Europe, Middle East and Africa CEO, as CEO of PHD Worldwide. 

Based in London, Marks begins his role Oct. 1 and will report to OMG Global CEO Florian Adamski.

“By enabling our agencies to quickly identify, adapt and respond in real time to the challenges of a dramatically changing consumer marketplace, [Marks] has unlocked growth for our clients and made OMG the No. 1 media agency group for net new business in the EMEA region for the year-to-date, according to the most recent COMvergence reporting,” Adamski said in a statement.  

Marks joined OMG in 2014 after Omnicom acquired Mobile5, the global UX, design and tech consultancy service that he co-founded. As CEO of OMG EMEA, Marks helped create Omnicom’s Transact commerce and retail media consultancy and helped expand OMG’s TRKKN analytics and cloud consultancy to 20 markets across Asia Pacific, EMEA and North America.

His successor at OMG is expected to be named next week. 

Marks succeeds Philippa Brown, who has spent the last 16 years in leadership roles with OMG, most recently as global CEO. Brown is leaving the agency to pursue independent corporate and advocacy consulting work. 

During her tenure, Brown helped secure the Diageo, Chanel, Unilever and the $300 million Grupo Bimbo accounts. She also launched and led OMG’s Talent Management Community. 

“We are deeply grateful for her tireless leadership, creative vision and unwavering commitment to meeting the needs of her clients and her people, and we wish her all the best as she redirects her singular energy, experience and expertise to an exciting new chapter in her career,” Adamski said in a statement. 

In May, PHD changed up its U.S. leadership when it replaced CEO Catherine Sullivan with U.S. Chief Operating Officer Mike Solomon.