The paper outlines the methodological framework in which the attitude to uncertainty and risk is rational and allows, under conditions, to make prudent decisions aimed at achieving goals. The fundamental difference between the conditions of uncertainty and risk is shown. An interdisciplinary definition of risk is proposed that is not associated with any science or group of sciences. The definition is based on the idea that risk is a consequence of decisions made by a person based on his goals, assessments, and value system. The significance of normative risk assessment models is shown, since they serve as guidelines and a methodological basis for actions for a person facing difficult choice problems. Risk assessments of rare events are considered, and in particular, it is shown that they occur more often than is commonly believed