Let's face it: some days you just don't want to wear heels. Then there are those other days when you actually do want to wear heels, but end up succumbing to flats once your dogs start barking. Either way, flats lend a stylish dose of Parisian-chic to a pair of basic skinny jeans — and can make everything from printed trousers to floaty dresses look cool and casual, too. Style setters like Jessica Alba, Heidi Klum, Taylor Swift, and more look impossibly laid-back and effortless while running errands around town, and Rosie Huntington-Whiteley and Miranda Kerr proved that airport comfort can also be incredibly glamorous, too. Click through for 15 celebrity examples of fab flats, then shop some of our editors' picks.