Ketchum president Barri Rafferty will become CEO of the Omnicom unit on Jan. 1, taking over for Rob Flaherty, who will remain chairman.
She will become the first woman to lead a Top 5 global PR firm, according to Ketchum's release.
Before assuming the president post in 2016, Rafferty led North America and the global brand marketing practice. She helped launch Ketchum Digital and counseled top clients such as Gillette and Pernod Ricard.
“Barri brings strong business acumen, a passion for operational excellence, and a deep belief in the importance of talent, especially the critical role of diversity, equity and inclusion. I know these skills will help her lead the agency forward,” Karen van Bergen, Omnicom PR Group CEO, said in a statement.