Interstellar bubbles were proposed in the 70's to explain the Copernicus detection of interstellar OVI absorption lines. A variety of bubble models are available, but the model by Weaver et al. (1977) is by far the most well-cited. In their pressure-driven bubble model, a bubble consists of a dense shell of swept-up ambient medium and its interior is filled with shocked fast wind at X-ray-emitting temperature. At the interface between the hot interior gas and the cool nebular shell, heat conduction takes place and produces a layer of 10^5 K gas, where highly ionized C, N, and O exist. To critically compare the physical structure of wind-blown bubbles with theoretical models, multi-wavelength observations are needed. The advent of Chandra, XMM-Newton, and FUSE finally made it possible to see the hot gas in bubble interiors. I will discuss why we see so few bubbles at visible wavelengths, and report X-ray and FUV views of bubbles.