This volume is a collection of the papers presented at the International Seminar on Advanced Nuclear Energy Systems toward Zero Release of Radioactive Wastes, which was held in Japan in November 2000. Scientists and engineers working in academia, research organizations and industry came together to discuss the role and contributions of nuclear energy to the environmental issues in the new millennium. It provided a forum for open discussions about the pursuit of solutions for the reduction of nuclear wastes based on the accelerator and fusion technologies, in addition to the advanced fission technology to harmonize the nuclear energy systems with the global environment. It also promoted future international collaboration in the following research fields: the role of nuclear energy in the new millennium; waste management; transmutation of minor actinides and fission products; advanced fission systems, accelerator driven systems, fusion systems, nuclear database, and advanced nuclear fuel cycles for transmutation of wastes. Published originally as a special issue (volume 40/3-4) of the international journal Progress in Nuclear Energy.