Bevan will switch from Glamour publisher Conde Nast to join IPC Southbank on September 18.
She will report to Marie Claire editor Marie O'Riordan, who said: "Carla is a human dynamo of energy and ideas and I am really looking forward to working with her to ensure we quickly become the first destination for fashionable women online."
In addition to working on the five-year-old , Bevan has written for , , More! magazine and Metro.
IPC Southbank launched in May and is preparing to revamp the magazine product when its November issue goes on sale on October 5.
The magazine will tighten its focus on thirty-something readers in reaction to its 10.9% drop in circulation against a 1.6% overall drop for the women's lifestyle and fashion sector. Marie Claire sold around 331,127 copies in the first half of this year, around 40,000 fewer copies than the second half of last year.
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