Since 1930, the World Energy Council (WEC) has been closely involved in problems associated with the use of nuclear power. At the meeting then held by the WEC Executive Committee in Berlin, Albert Einstein drew the attention of power utilities to this new source of energy. In addition to optimized use, technical progress, and waste management, the WEC regards aspects of safety, proliferation, and sustainability of nuclear power as matters of special importance. In the energy scenarios elaborated by the WEC since the 1980s' nuclear power plays one of the leading roles in the future energy mix. The sustainable management of energy resources, worldwide climate protection, but also equal access to energy for all people, require the use of nuclear power and the furtherance of its options. Moreover, the use of nuclear power in the industrialized countries helps to stabilize energy prices worldwide. This is in the interest especially of developing countries, for which low-cost, accessible energy sources are vital factors. The electricity supply crisis in California in 2001 has shown the continuity of supply to be one of the factors important in the deregulation of energy markets. Bottlenecks in electricity supply because of a lack of acceptance of electricity generation are problems affecting the future of industrialized countries. For instance, the increasing digitization of everyday life demands reliable power supply. In its studies of all available energy sources the WEC found no alternative to nuclear power. Factors of importance in the future development and use of nuclear power are public acceptance and the ability, and willingness, to take decisions in economic issues. Waste management, proliferation, safety, and research and development are other priorities. As a source of power protecting the climate, stabilizing costs, and offering a considerable potential, nuclear power is compatible with the objectives of sustainable development for the world of tomorrow.