Developing ways to manage terrorism effectively requires a better understanding of how the public perceives this threat. In the present study, Canadians' perceptions of terrorism risk and 4 other hazards were assessed using a word-association technique and rating scales reflecting key cognitive dimensions of risk (threat, uncertainty, control) and worry reactions. Data were collected in a national telephone survey. Canadians perceived terrorism as posing a lower threat, as more uncertain, and as less controllable, compared to the other hazards. Positive associations of perceived threat and of perceived uncertainty with worry about terrorism were observed. However, perceived control was unexpectedly positively associated with worry about terrorism. The findings also suggest that additional social contextual factors should be examined in future research.