Electrical phenomena have been studied in biology for nearly two centuries. Only recently, however, thanks to co-operation between biochemists, electrochemists and electronic engineers, have we begun to understand in any detail some of the many ways in which electronic and ionic charges are transferred and distributed in biological systems. Many of the essential processes that sustain life - energy conservation reactions, enzyme catalysis, biological communication systems, ion transport and osmotic effects rely on gross or subtle changes in charge configuration on and around biological molecules. Interdisciplinary studies in bioelectronics therefore shed light on many of life's fundamental processes, but they also underlie the exploitation of these phenomena in a new generation of bioelectronic devices. This book explores these themes at an introductory level suitable for senior undergraduates or postgraduate students in biochemistry, biophysics, biotechnology and electronics.