This book provides an overview of recent advances in radiation oncology, many of which have originated from physics and engineering sciences. The new technologies in this field have a complex physical, mathematical and technical background that technical assistants, dosimetrists, and physicians frequently find difficult to comprehend. However, this book is specifically designed to be readily understandable by professionals and students with a medical background as well as by newcomers to radiation oncology from the field of physics. All relevant areas of the subject are covered in detail, including 3D imaging and image processing, 3D treatment planning, modern treatment techniques, patient positioning, and aspects of verification and quality assurance.