First published in 1989, this book provides a comprehensive review of the detection techniques that are used in X-ray astronomy. Since the first discovery of a cosmic X-ray source in 1962, there has been rapid growth in X-ray astronomy, which has largely been made possible by enormous advances in the capabilities of photon counting instrumentation. The book describes the first 25 years of astronomical X-ray instrumentation and summarises the areas of current detector research, giving particular emphasis to imaging devices and to non-dispersive devices of high spectral resolution. It is the first book to give such a comprehensive treatment of the subject, and will provide astronomers with a valuable summary of detection techniques.