The 462-page issue, out today, will feature Barrymore on the cover, interviewed inside by Diaz, and featured again in a 10-page picture portfolio shot by Elle photographer Mark Seliger.
As part of the launch, Elle has secured 26 one-off pieces from the world's top designers, including Mulberry, Dior, Versace, Burberry, Armani, Dolce & Gabbana and Prada, to be auctioned on eBay to raise money for the Breast Health Institute -- a charity dedicated to breast cancer research and treatment.
Elle's original cover girl Yasmin le Bon, wife of Duran Duran singer Simon, models some of the designer pieces created for the charity auction.
Lorraine Candy, Elle editor-in-chief, said: "This iconic fashion monthly is all about how you wear it, not what you wear and that holds true for young women as much today as 21 years ago. It was an honour having Donatella so involved in the issue and she brought some big names to the magazine."
Earlier this year, Hachette Filipacchi UK launched Elle Collections, a guide to the coming season's catwalk collections, with a print run of 50,000.
Former Cosmopolitan editor Candy took over as editor of Elle two years ago as the magazine launched its handbag-sized edition in central London and airport and station outlets.
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