Several countries are currently discussing whether they will rebuild their nuclear power stations in order to continue this type of energy production in the future. The public, with its own opinion about nuclear power stations, has an influential voice in this discussion. As a result, policy makers and nuclear scientists are interested in the public's perception of nuclear power and in what determines this perception. We therefore examined an explanatory model of the public's acceptance of nuclear power based on a telephone survey among a representative sample in Switzerland. The model included such factors as risk perception, benefit perception, affective feelings, and social trust. Moreover, we distinguished between two types of benefit perception: benefit for the climate and a secure energy supply. The model fitted very well to our data and explained acceptance very well. Acceptance was mainly influenced by perceived benefits for a secure energy supply and, to a lesser extent, both by perceived benefits for the climate and by risk perception. Affective feelings about nuclear power appeared to be a central factor in the model. Implications for communication about nuclear power stations and for further research are discussed.