For years, ill-fitting short sleeve button-down shirts conjured up images of nerdy guys like Dwight Schrute or Mormon missionaries. But they've been gathering steam with stylish gents for the past few years and this summer, it seems like brands big and small are offering sharp takes on this warm weather staple. Cut from lightweight cottons with a more streamlined fit, they make for a nice alternative to your everyday polos and T-shirts. They come in a wide range of colors and styles, but we're partial to the bolder patterned varieties, like these featured here. From a cheeky nautical print and exploded patterns to classic madras plaids and stripes, they're cool and casual—which means you don't need to tuck them in. And don't be afraid to cuff the sleeves once or twice. But remember, if you're going to be flashing some bicep, make sure to prepare accordingly.