Emery currently leads strategy, client service and product development for Mindshare globally and is also the chief strategy officer for GroupM worldwide.
Emery and Proctor have worked together since Mindshare was founded as a global network in 1997. Emery will now focus solely on Mindshare and its clients.
He set up Mindshare with Proctor in 1997 as strategic development partner for Mindshare Worldwide. In his new role, he will take over responsibility for the agency's activities in 112 countries, overseeing more than 5,000 employees.
Emery's career began in the media department of Ogilvy in 1992 and he rose to become the European planning director and deputy managing director of the network.
The latest announcement was made by GroupM Global CEO Irwin Gotlieb, who now steps up to the position of chairman of GroupM. Proctor will continue to report to Gotlieb.
Emery said: "I'm delighted to be taking on this role at this exciting time in the agency's evolution.
"Mindshare's agenda continues to focus on innovation, technology and added value to our clients, and we want to build on the successes of recent years. The success of Mindshare has always been built upon our network, teamwork and willingness to embrace change.
"We will continue to increase investment in a diverse and talented team across a global network that is second to none. We're confident that our clients and staff will prosper as a consequence of these changes – our rate of growth and the complexity of our business require that we constantly evolve."
Proctor said: "I am delighted that Nick has agreed to take over. Nobody has done more than him to help build Mindshare and I know that the agency will go from strength to strength under his leadership."
Emery was also one of the key orchestrators of Mindshare's global restructure that kicked off in April 2008.
One of his first tasks will be to address the $3bn global Unilever media review. The account is currently split between Mindshare, PHD and Initiative in different territories. Mindshare holds the prestigious Western European media business for the FMCG giant.
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