Nuclear power plants worldwide make important contributions to energy production. A total of 439 plants are in operation; with nearly 10 000 years of operating history, they reliably provide some 16 percent of the world's electricity production. The growth rates of nuclear power expansion in the seventies and eighties are no longer achievable now. Growing operating experience and further optimization of plant operation have caused the electricity generation in existing plants to grow overproportionally, corresponding to a calculated equivalent of 28 000 MW of capacity increment in the nineties. The short-term perspectives of nuclear power generation until 2020 as outlined by the International Energy Agency (IEA) indicate a slight decrease of electricity production with a variety of different regional developments. Over the same period of time, there will mainly be further improvements in reliable operation, resulting in higher availability and added safety, as well as measures extending plant life. Studies going beyond the time frame of the IEA Study forecast a major increase in nuclear generating capacity for the period after 2020 up to 2050. The foreseeable long-term developments on the world energy markets, with their limited fossil energy resources, are seen as a reason why nuclear power and renewable energies jointly will be important components in meeting energy requirements and, simultaneously, fulfilling the needs of climate protection. Specific problems of nuclear power, which can be solved, are seen to be the development of innovative plants, a stable cost situation, and the reduction of economic risks because of the long periods of payback of the capital invested.