Methods involving nuclear physics are today finding applications in many disciplines, including important areas of medicine. This book intends to bridge the gap between the many applications in medicine and the underlying basic nuclear physics which needs to be understood by those applying the methods. In addition, those active in nuclear science will gain insight into the manifold applications of their subject. The main topics of the book are: physical foundations, instrumentation, diagnostics (imaging), therapies and radiation safety. The book will appeal to medical doctors active in nuclear medicine as well as to medical physicists.