"Both ballet and fashion are art forms about making something beautiful," says New York City Ballet principal dancer Janie Taylor. "They can really complement each other's work." The evidence? Costumes designed by Prabal Gurung, Olivier Theyskens, and Iris van Herpen for NYCB's 2013 Fall Gala in September, and Joseph Altuzarra, Valentino, J. Mendel, Rodarte, and Stella McCartney in seasons past. The designers who aren't creating garments for the stage are swirling ballet into their collections, from tutu-style skirts at Balmain to tie-up pumps at Ralph Lauren. When the two worlds collide, the result is the most graceful trend of the season, barre none. —Jessica Minkoff "Trevor Undi"