Drawing together topics from a wide range of disciplines, this text provides a comprehensive insight into the fundamentals of magnetic biosensors and the applications of magnetic nanoparticles in medicine. Internationally renowned researchers showcase topics ranging from the basic physical principles of magnetism to the detection and manipulation, synthesis protocols and natural occurrence of magnetic nanoparticles. Up-to-date examples of their clinical usage and research applications in the biomedical fields of sensing by diverse magnetic detection methods, in imaging by MRI and in therapeutic strategies such as hyperthermia, are also discussed, providing a thorough introduction to this rapidly developing field. Each chapter features questions with answers, highlighted definition boxes, and numerous illustrations which help readers grasp key concepts. Mathematical tools, together with key literature references, provide a strong underpinning for the material, making it ideal for graduate students, lecturers, medical researchers and industrial scientific strategists.