This French label has been around since 1889 and is the oldest French fashion house still in existence. With Alber Elbaz at the helm, Lanvin's signature look is fluid and sexy; think one-shouldered cocktail dresses, cigarette pants, and ruffled blouses. This elegant town house is the first U.S. outpost. The interior design itself is a showstopper; the three-story space oozes old money and glamour with its Art Deco chandeliers and soothing gray walls. And the clothes? Just as slinky.