Can you imagine Anna Wintour without her bob? What about Gwen Stefani sans her ever-present red lip? While some celebrities relish the opportunity to change up their look every other week (see: Katy Perry Miley Cyrus ), others have zeroed in on what they look — and feel — their best in, and keep it that way for eternity. (Okay, at least a few years. Or, in Wintour's case, 49).It's those looks we see over and over again that we just can't get enough of: They're reliable, they're gorgeous, and they've essentially become trademarked by the stars who rock them. Think of it as the beauty equivalent of the uniform Wonder how these high-profile women happened upon their signature beauty look? Click ahead, and you'll find everything you need to know.