Theory has challenged three stylists from their Fashion Insiders campaign—J. Errico, Dani Stahl and Annabel Tollman (pictured left to right)—to compete in a fashion battle to benefit the charity of their choice. The concept is simple: Each stylist must use pieces from the brand's new summer collection to create three unique looks. The winner will be announced on July 10th and receive $2,500 for charity. (Tollman is competing for OXFAM America, J. Errico is representing the Hetrick-Martin Institute, and Stahl is vying for the Animal Rescue Fund of the Hamptons.) See all the looks in our gallery, get some summer style inspiration, then vote for your favorite on Theory's Facebook page. Or, if you're in Hamptons this weekend, head over to the East Hampton Theory store, where you can enter to win a $750 gift card when you cast your vote.