Martin and Munns replace Simon Darwell-Taylor, who parted company with the agency in October after just ten months in the job. Darwell-Taylor left to join Big Picture - the agency founded by the former DLKW Dialogue chairman Simon Andrews - as a creative partner.
Martin, a copywriter, and Munns, an art director, joined the UK office of Arc Worldwide in 2002.
They have since collected more than 30 awards for work on Fiat, Great Ormond Street Hospital and Ariel. Their gongs include a silver at the Campaign Direct Awards for the Fiat "coathanger" campaign in 2003.
Last year, Munns and Martin were the creative directors on the Ultrasound mailing for Great Ormond Street Hospital, which won the 2005 Grand Prix at the Direct Marketing Awards and two silvers at the Campaign Direct Awards.
Mike Spicer, Arc Worldwide UK's managing director, said: "As the team that has been largely responsible for keeping Arc's creative standards high over the past year-and-a-half, they were the stand-out candidates."
Munns said: "We believe that Arc is truly committed to producing big ideas executed across multiple disciplines, and we are looking forward to developing those big ideas."
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