The updated, second edition of the textbook Applied Physics for Radiation Oncology, originally published in 1996 is intended for both radiation therapists and students of radiation therapy. Chapters cover treatment planning, photon and electron dosimetry, brachytherapy, methods of dose calculation, isodose curves, beam-modifying devices, patient and beam geometry, radiation protection, and clinical use and operation of linear accelerators. The authors unify the principles of radiation therapy physics with the real world of clinical practice. A must for radiation therapists.