Carat won the award after competing against 11 other agencies on behalf of their respective clients. The agency was presented with the award by the National Magazine Company at the Saatchi art gallery in Kensington this morning.
The shortlist, announced last week, included: MediaVest for P&G, Clear Blue; Mindshare for Ford Fiesta; Carat for Nivea; M2M for Estee Lauder; MEC for Next; and Red C/MediaVest for Marisota.
Other shortlisted agencies were: ZenithOptimedia for L'Oreal; V&R for Flowerbomb; Vizeum for Pure; Manning Gottlieb OMD for John Lewis; and Walker Media for M&S Beauty.
Carat's winning multimedia campaign, "Celebrating heritage", focussed on the current resurgence of vintage and retro fashion.
In June, the National Magazine Company, in partnership with Campaign and Media Week, launched the competition for the UK's media and creative agencies as part of the publisher's centenary celebrations.
The NatMag 100 Award is a new initiative that gives agencies and their clients the opportunity to win a multimedia ad campaign across the entire NatMag portfolio of 24 brands, including Harper's Bazaar, Good Housekeeping, Cosmopolitan, Esquire and Men's Health. The campaign will run across print and online.
As part of the NatMag 100 Award, media and creative agencies were invited to devise the most innovative, creative ad campaign for an individual brand, utilising a combination of the brands in the NatMag portfolio and platforms to target women or men in the UK.
Arnaud de Puyfontaine, NatMag chief executive, said: "Congratulations to Carat and Debenhams for winning the NatMag 100 Award.
"The agency's 'Celebrating heritage' campaign for Debenhams not only demonstrates confident multimedia thinking, but utilises our brands in new and innovative ways.
"It is a brilliant concept which we’re looking forward to seeing implemented in 2011."
The award was judged by a panel including: John Wilshire, head of Innovation at PHD; Nigel Sharrocks, chief executive of Aegis; Philippa Brown, CEO of Omnicom; Jane Ratcliffe, chief executive of MediaCom; Simon Matthews, partner of Polestar Communications; Claire Beale, editor of Campaign; and Ivor Falvey, group commercial director of Haymarket.