The provision of electricity has been a great benefi t to society, particularly in health terms, but it also carries health costs. Comparison of diff erent forms of commercial power generation by use of the fuel cycle methods developed in European studies shows the health burdens to be greatest for power stations that most pollute outdoor air (those based on lignite, coal, and oil). The health burdens are appreciably smaller for generation from natural gas, and lower still for nuclear power. This same ranking also applies in terms of greenhouse-gas emissions and thus, potentially, to long-term health, social, and economic eff ects arising from climate change. Nuclear power remains controversial, however, because of public concern about storage of nuclear waste, the potential for catastrophic accident or terrorist attack, and the diversion of fi ssionable material for weapons production. Health risks are smaller for nuclear fusion, but commercial exploitation will not be achieved in time to help the crucial near-term reduction in greenhouse-gas emissions. The negative eff ects on health of electricity generation from renewable sources have not been assessed as fully as those from conventional sources, but for solar, wind, and wave power, such eff ects seem to be small; those of biofuels depend on the type of fuel and the mode of combustion. Carbon dioxide (CO 2 ) capture and storage is increasingly being considered for reduction of CO 2 emissions from fossil fuel plants, but the health eff ects associated with this technology are largely unquantifi ed and probably mixed: effi ciency losses mean greater consumption of the primary fuel and accompanying increases in some waste products. This paper reviews the state of knowledge regarding the health eff ects of diff erent methods of generating electricity.