Native New Yorker, Zac Posen, isn't as old as some of his fashionable elite. Nevertheless, the young designer has managed to create quite a name for himself since the launch of his eponymous line in 2002. 

Best known for his incorporation of 1940s glamour in mermaid gowns and mini-dresses, Zac Posen has drawn a following with not only young East Coast socialites, but Hollywood starlets as well. 

The designer, known for making the best party dresses, won a coveted internship at the Metropolitan Museum of Art's Costume Institute before studying abroad at Central Saint Martins in London. Upon his return to the states he was offered positions at luxury fashion houses LVMH and the Gucci Group. Since then, Posen has been awarded for his exquisite work, receiving the Swarovski-Perry Ellis Award for Womenswear from the CFDA. 

Celebrity clients include Gwyneth Paltrow, Beyonce, Lucy Liu, Natalie Portman and Naomi Campbell, among others. Posen most recently dressed Kelly Osbourne for the 2011 Golden Globe awards.