To assess the significance of the election rejecting restrictions on nuclear power development in California, the authors used a two-stage panel survey of over 1000 adults to study attitudes toward nuclear power and Proposition 15, the nuclear power plants initiative. Most survey respondents knew very little about nuclear power plants, but knowledge was almost entirely independent of evaluation of nuclear power. Opposition to nuclear power follows primarily from an internally consistent set of beliefs about the general riskiness of nuclear power plants. The belief most highly correlated with evaluation is the individual's assessment of the likelihood that radioactive waste will harm future generations. There was no evidence that opposition to nuclear power is part of a strong, well-defined ideology encompassing other issue positions, nor of strong links between attitude toward nuclear power and social background characteristics.