Ready to get waisted? This season, celebrity trendsetters are cinching their little dresses with chunky brown belts. Sarah Jessica Parker chose a belt from her own Bitten line to dress down an Akris cocktail number, while Rachel Bilson buckled one on over a T-shirt dress from Twelfth Street by Cynthia Vincent. "Brown is a great transition color for fall," says her stylist Nicole Chavez. "It adds a little element of boho without being costumey." She recommends pairing the look with a sweater dress and boots when the temperature drops. "Just make sure your belt doesn't have any bedazzlement," says Chavez. "Go clean and simple and it'll look modern."

—Betony Toht