Major improvements in instrumentation and specimen preparation have brought SEM to the fore as a biological imaging technique. In FESEM, a field-emission cathode placed in the electron gun of a scanning electron microscope provides narrower probing beams and high electron energy. The result is improved spatial resolution and minimized sample charging and damage. Images produced are less destroyed and have a spatial resolution down to 1.5 nm, three to six times better than conventional SEM. Although this imaging technique has undergone tremendous developments, it is still poorly represented in the literature, limited to journal articles and chapter s in books. This comprehensive volume is dedicated to the theory and practical applications of FESEM in biological samples. It provides a comprehensive explanation of instrumentation, applications, and protocols, and is intended to teach the reader how to operate such microscopes to obtain the best quality images.