Global inventories of spent nuclear fuel are expected to increase substantially in future years. Because of the widely accepted international principle of whoever generates the waste also is responsible for its safe and secure disposal, the focus for the long-term management of highly radioactive waste has been on national disposal efforts. The authors of this book examine the variety of international conventions used to help monitor and regulate national radioactive waste management efforts and establish international norms. Furthermore, this book examines the present nuclear fuel cycle, the minor actinides (MAs) which have been generated in light water reactors (LWRs) and which remain in the high-level radioactive waste. The long-term geological disposal of this waste, which may affect the environment, is examined as well. In addition, this book is dedicated to problems of elaboration of technology and apparatus for producing oxygen-free ceramic materials as applied to, predominantly, needs of nuclear power engineering. The promising strategies in development of crown-containing extraction systems for acidic radioactive waste reprocessing are discussed as well. The examples of the crown-based system applications in the solution of particular radiochemical tasks in USA, Russia, France and China are also presented.