Jessica Simpson - The Jessica Simpson Collection

(credit: Frederick M. Brown/Getty Images)

Gwen Stefani - L.A.M.B.

(credit: Imeh Akpanudosen/Getty Images)

Mary-Kate and Ashley Olson - The Row

(credit: Stephen Lovekin/Getty Images)

Victoria Beckham - The Victoria Beckham Collection

(Photo by Rob Kim/Getty Images)

Kimora Lee - Baby Phat

(credit: Frazer Harrison/Getty Images)

P. Diddy - Sean John

(Photo: VALERY HACHE/AFP/GettyImages)

Sienna Miller - Twenty8Twelve

(credit: Ben Pruchnie/Getty Images)

Nicole Richie - House of Harlow 1960

(Photo by Marianna Massey/Getty Images)

Beyonce - House of Dereon

(credit: Beyonce Knowles/Getty Images)

Justin Timberlake - William Rast

(credit: Kevin Winter/Getty Images)