Zac Posen
Who’s worn it: Lena Dunham, Coco Rocha, Naomi Watts, Amanda Seyfried, Jessica Biel, Lea Michele, January Jones, Glenn Close, Tina Fey
Who he is: Of course we all know Zac Posen. He’s been around for years, but has definitely seen a resurgence recently–both in his business and his red carpet dressing. His clients have been exclusively A-list, from Lena Dunham (whom he used to babysit) to Glenn Close.