Sustainable nuclear energy dilemmas represent options based on the specific feature of the nuclear routes. Essentially, the dilemmas are based on the specific characteristic of nuclear material and technology for its processing. It also reflects on the nuclear material utilization, namely for electricity production in power plants, nuclear arm design, radioactive waste and transuranium use. Same dilemmas are based on the sustainable and unsustainable characteristics which can be utilized for the economic, environmental, and military use. The discussion in this book of potential use of the sustainable nuclear energy is focused on following dilemmas, namely: Nuclear resources dilemma is the substantial issue in the nuclear energy strategy. At the very beginning of the nuclear power development the main strategy has been adopted. Natural uranium strategy has been adopted as the potential use of natural uranium for the development of nuclear reactor concept. The vast majority of world’s energy in the coming centuries will come from a few sources: fossil fuels, the Sun, biomass, wind, geothermal sources, nuclear fission, and (potentially) nuclear fusion. Because the anticipated demand is high and because different technologies are better for different applications, it is likely that all of these sources will be tapped.