The scene at Cannes shifted beyond the Lions, Tweets and soirees for a tick as the United Nations, the International Advertising Association and a host of agencies today announced the launch of "Hopenhagen," a global marketing effort aimed at encouraging citizens to participate in the December U.N. Climate Change Conference (COP15) in Copenhagen.

Among the agencies throwing their socially conscious weight into the effort are Dentsu, R/GA, McCann Worldgroup, Digitas, Tribal DDB and many more. Leading the creative execution in the effort, meanwhile, is Ogilvy & Mather along with digital direction from Colle+McVoy.

According to the press statement, the campaign's creative materials "will emphasize the need to shift from 'coping' or ignoring our global challenges to 'hoping' and ultimately acting to create a new reality."

With cautious optimism in tow, the parties have already unveiled outdoor elements at Cannes as well as JFK, Los Angeles and Heathrow airports. But the official campaign hub rests at Hopenhagen.org, a minimally structured site that lets visitors type in their personal message of hope, read about the COP15, follow its Twitter and join the movement itself.

UPDATE: With so many agencies attributed to this endeavor, there was bound to be some drama. An anonymous agency source connected to the project claims that while all the holding companies involved were invited to pitch creative ideas to the UN, Ogilvy drew out its knives and won out over its fellow Omnicom brethren by sealing deals behind their backs.

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