This article discusses risk behaviors, seemingly voluntary actions of individuals that have adverse health consequences. The central theme is to examine these behaviors from two contrasting perspectives, that of the individual and that of the population as a whole. It is argued that distinguishing between individual and population views is important for understanding and interpreting health risk data, for developing conceptual and theoretical models for explaining these behaviors, and for devising intervention strategies to modify them. It is argued that an appreciation of both the individual and the population perspectives is important to developing effective action strategies for reducing these behaviors as public health problems.