Caroline Foster Kenny, chief executive of IPG Mediabrands EMEA, has tasked Morris with transforming the agency’s offering in the UK.
Initiative’s headcount has dropped by more than two-thirds in the past two years after the agency lost Tesco’s £90m UK media business in 2015, ending a 20-year relationship.
Morris, who will report to Foster Kenny and Initiative global chief executive Mat Baxter, had only just been promoted to global client president at Dentsu Aegis in January.
He was previously chief growth officer from June 2016. Before that, Morris was Vizeum’s UK managing director for almost four years and was credited with pushing the agency towards more digital, data and CRM output.
Morris also worked at Vizeum’s sister agency Carat in various planning roles, working his way up to deputy managing director after joining as a graduate in 1994.
He said: "I’ve spent most of my career helping to evolve agencies and I am driven by client success and agency growth through strategy and innovation.
"The chance to do this for Initiative, who have just had a global rebrand and new positioning put in place, is something that I am really looking forward to."