This is a basic teaching book for radiation oncologists, radiation physicists, and radiobiologists, setting out concisely the biological basis of radiation therapy. Early chapters deal with essential areas of science, including cell proliferation in tumours and normal tissues, principles of radiation cell killing, theoretical and modelling approaches and molecular aspects of radiobiology. Subsequent chapters deal with the applications of radiobiology to clinical radiotherapy. The principles of fractionation are described in detail, leading to the rationale of current approaches to the improvement of radiotherapy schedules. Also discussed are efforts to beat hypoxia in tumours, brachytherapy, the principles and use of particle beams, the combination of radiotherapy and chemotherapy, hyperthermia, targeted radiotherapy, and current efforts to individualize treatment with radiation therapy. This second edition uses the same clear and concise style as the first, maintaining a high ratio of charts to text, for the benefit of those who have a visual memory. The text has been fully updated and expanded to include recent advances in molecular growth which will be of particular importance to trainees and professionals alike. The charts of this second edition have been substantially revised and each chapter concludes with a series of Key Points. There are frequent cross-references between chapters and a glossary of scientific terms is provided.