The present book describes the various processes involved in different stages of the entire nuclear fuel cycle, which include exploration of uranium, thorium, and other nuclear materials, mining and milling of ores, conversion of the separated nuclear material into nuclear grade, fabrication of different types of nuclear fuels and their physical as well as chemical quality control, thermodynamics of the interaction among fuel and fission products during reactor operation, post irradiation examination, spent fuel reprocessing, radioactive waste management, accounting and control of nuclear materials, and safety aspects involved in handling and transportation of nuclear materials. The book provides the fundamental knowledge to the practicing nuclear scientists and engineers, young researchers, and postgraduate students interested in pursuing a career in nuclear industry in general and those engaged in human resource development in the field of nuclear science and technology in particular. It can also be prescribed as a textbook for a course on nuclear fuel cycle at postgraduate level.