The appointment ends a long search that followed the departure of Dare's creative director, James Cooper, to join Another Anomaly in New York in November 2007.
Dare had appointed Andy Amadeo, a former executive creative director of Mustoes and CDP, to replace Cooper, but he left after just four months.
In his new role, Brian Cooper takes creative leadership across a number of the agency's clients, which include Vodafone and Sony Ericsson.
The copywriter joins Dare after a two-year stint freelancing at Mother and, before that, he was a creative director at McCann Erickson. During his tenure, he picked up a silver at the Campaign Press Awards, two silver BTAA awards and a silver Campaign Digital gong, all for work on the MasterCard brand.
Separately, Dare has been named as a lead digital agency for the Football Association after a pitch against undisclosed agencies.
The FA has briefed Dare to develop its online presence in the lead-up to the Fifa World Cup in 2010.
Its first task will be to redesign the England website, which forms part of the FA's main website, TheFA.com. In addition to the website, Dare will produce a one-off campaign to promote the game.