Remarkable advances in the area of biosensors have been fueled by explosive developments in miniaturization and nanotechnology. This book provides a comprehensive guide for academics, professionals, and postgraduates to the growingly relevant field of biosensors. Covering the fundamentals, it presents a wide range of biosensing approaches and discusses the latest developments in the field. It also explores applications of biosensing systems and devices, including microscale and nanoscale devices, in clinical, environmental, food, and biodefense analysis. In addition, the text addresses emerging challenges and their implications for researchers, technologists, and industrialists.