This third edition has been throughly updated and expanded, prompted by the success of the second edition. Supplemented with tables and illustrations throughout the book, each chapter provides the reader with well-delineated descriptions of the different aspects of physics and radiation biology related to nuclear medicine. The second edition was successful and highly acclaimed, as Dr. Saha made many complex concepts readily understandable for residents and practitioners in nuclear medicine and radiology as well as technologists. The book serves as an excellent text for those preparing for their Board and Registry examinations. Special features in the Third Edition include: statistical tests: the Chi-Square test and the evaluation of diagnostic tests; new chapter on software and DICOM; extensive updates on SPECT/CT cameras; new chapter entirely devoted to PET; expanded chapter on cellular damage by radiation and on dirty bomb and radiation phobia; new revised NRC regulations.