Gordon adds responsibility for the UK agency to his role as chief executive of the Rapp Collins Europe, which he took on last July.
He will be assisted by managing director Mike Larmer, along with creative director Ian Haworth and managing partners Steve Grout and Paul Alexander.
Coleman joined WWAV in March 2001 as managing director from WWAV Scotland. The agency then restructured, splitting into four client-focused divisions to enable it to strengthen its relationship with customers, and Coleman took over from Gordon as chief executive.
Gordon said Coleman's strategic vision has been "vital in ensuring that we understand the pressures our clients face and our need, in turn, to deliver greater pace, quality and efficiency".
"We are now structured in a way that can deliver against that promise. But, having established this strong platform, we have agreed that it is now time for the team to take us on to the next stage of our evolution. I would like to thank Adam for his contribution, both here in London and in Scotland, and wish him well for the future," he said.
The overhaul follows a turbulent 12-month period for WWAV, which has seen it lose some high-profile accounts including Toyota last summer and, more recently, the £4m BT Business account. It is currently defending the £7m media and creative accounts for Legal & General.
It has cushioned the blow of some of these losses, however, with wins including Lloyds TSB Trustcard, YMCA, NTL's £7m media brief and the £5m WWF creative brief won in a joint pitch with BMP.
"Clients are under greater pressure than ever to get their products and services to market in a way that will generate maximum return on investment," Gordon said.
"The emphasis has to be working smarter for clients and on a culture based on continuous improvement. I am looking forward to working with the management team and clients to ensure we continue to deliver against this blueprint."
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