How does a quantum well detector, a silicon BIB or a CCD work? How are heterodyne techniques used in infrared detectors and submillimeter receivers? And how do you specify the performance of any detector system? This volume answers all these questions with an up-to-date review of all the techniques for the detection of radiation. This presentation approaches detectors from the perspective of the underlying physics; and in this way it provides a unified understanding of the detection of radiation in the ultraviolet through to the submillimetre. Clearly worked examples demonstrate the physics involved and problems are provided to increase the reader's knowledge of how each system works. This clearly written and authoritative review of modern detector systems will develop the understanding of final year undergraduate and graduate students, and will provide a valuable reference for professionals in astronomy, engineering and physics.