Paris becomes them! L.A. girls Nicole Richie and Jessica Alba traveled across the Atlantic to attend Fashion Week in the City of Lights — and both have never looked more stylish.

Fashion Star judge Richie looked fantastic sitting front-row at Givenchy with A-listers Jessica Chastain, Amanda Seyfried, Kanye West, and Kim Kardashian, but it was her look for Stella McCartney's Fall/Winter 2013 show on March 4 that stood out. The petite 31-year-old rocked a perfect black and white striped dress by the designer that was both understated and bold.

PHOTOS: Remember when Nicole's style was more boho-chic?

Fellow Hollywood mom Alba, meanwhile, brought along 4-year-old daughter Honor on the trip, but the actress, 31, made sure to trade in her casual-chic mom attire for a more polished look at the fashion shows. At McCartney's runway show, Alba looked stunning in a crisp white button-down under a super-slim, tuxedo-inspired pant suit.

PHOTOS: See Jessica's bump style

Tell Us: Whose Paris Fashion Week look do you prefer?

This article originally appeared on Nicole Richie vs Jessica Alba at Paris Fashion Week: Who Looked Better?