"I'm quite thrifty, really. I love a sale," says designer Georgina Chapman. And although her evening wear collections, Marchesa and Notte by Marchesa, are luxurious, she's no clothing snob: "Designer clothes are great, but I also spend lots of time in Topshop" (the trendy, inexpensive British chain that's on its way to America). Here, basic tuxedo pants from Express ($80)—a terrific source of well-fitting, inexpensive trousers—are elevated by an asymmetrical black lace dress that's pure fantasy (Givenchy by Riccardo Tisci). A lavish piece like this is worth the splurge because it lifts whatever else you're wearing to a higher level—and you'll have it for years.
Earrings, Fred Leighton. Bracelets and ring, Lorraine Schwartz. Shoes, Fendi.