It is understood that Costerton is leaving without a job to go to. Richard Millar, CEO of H+K UK, and Lars Erik Grønntun, president H+K North East Central Europe, will assume Costerton’s responsibilities for Europe.
Costerton said: ‘This has been a hard decision to make. I committed to do the role for two years when I started in 2009 and have extended that to work through the management transition with [global chairman] Jack Martin.
‘During the past three years, we have done a root and branch review of the EMEA business and I’ve made a number of substantial new hires and promotions and put a leadership team in place, which I believe provides clients with great breadth and depth. That process is now complete and I think now is the right time to move on.’
Dave Robinson, who was appointed in June as president and CEO of H+K AMEASCA (Australia, the Middle East, Africa and South & Central Asia), will continue in his role.
Costerton has been at H+K for 12 years and has held other senior management positions, including three years as CEO of the company’s UK offices and a period as the firm’s head of technology, EMEA.
She is currently the elected chairman of the PRCA, a post she will hold until the end of 2012.
Costerton joined the company in July 1999 from technology boutique Abacus.
The news comes after the agency announced that it has rebranded to become Hill+Knowlton Strategies, a year after merging with US lobbying agency Public Strategies.