The "purple book" that helps residents and techs to prepare for the radiologic physics portion of board and registry exams is now in its Second Edition! Chapters outline key information and test the reader's understanding with board-type review questions, along with answers and rationale provided. It includes 500 multiple-choice questions. Topics covered include MRI, CT, US, mammography, radiography, fluoroscopy, nuclear medicine and more. New features include an 18 per cent larger text, more test questions at the end of each chapter, new and revised illustrations, and an expanded glossary. New chapters include those on image quality and dose, digital imaging and PACS, computers and mathematics, and a separate chapter on CT.