For the Romulans on the Narada, Kaplan wanted worn and rugged clothes because of their mining backgrounds. He found some aged, greasy-looking fabrics at a flea market, and commissioned the makers of the clothes (who were based in Bali) to create his designs using their fabrics. For the Vulcans, Kaplan designed costumes which shared the eloquent and austere qualities of the Vulcans themselves, while creating a new, corseted shape for the Vulcan women.
http://memory-alpha.org/en/wiki/Star_Trek_(film)
