A well-rounded wardrobe is going to contain a lot of different suit jackets, blazers and sport jackets, but none of them will see as much use as your favourite navy sports jacket. Why? Because a navy sports jacket is pretty much the easiest, most adaptable piece of clothing you can buy. Just throw it on over a t-shirt, a button-down or a crew-neck sweater, and your outfit instantly gets several degrees more polished.