This fully inclusive handbook focuses on the development of sensors to recognize substances rather than physical quantities. It examines devices that use a biological sensing element to detect and measure chemical and biological species as well as those that use a synthetic element to achieve a similar result. A first port of call for anyone with a specific interest, question, or problem relating to this area, this comprehensive source of reference serves as a guide for practicing scientists and as a text for many graduate courses. It presents relevant physics to chemists, chemistry to materials scientists, materials science to electronic engineers, and fabrication technology to all of the above.