Innerwear as outerwear—it's a recurring theme. Over the years, everyone from Dolce & Gabbana and Versace to Prada and Donna Karan have done dresses that look like slips. But as is often the case in fashion, what's old is new again. So it feels really fresh to us right now to see a few slips that serve their original purpose—and in an utterly chic way. Our picks? An exquisite one from Stella McCartney with just the right dose of sparkle, a simple lace number from Vera Wang lingerie and a nude, prairie-ish offering from Kiki de Montparnasse. And of course, now that spring is here, it's probably time for a tiny shot of color. One of the best: Eres' acid green silk version. Just the thing to have peeking out from under a frock.