the paper addresses conceptual and theoretical aspects of the construction of the category 'risk' within disciplines related to safety engineering, epidemiology, and actuary sciences. the role of molecular biology is highlighted in particular. repercussions are examined not only in psychological and sociocultural terms but also from the perspective of social communication. relations between the notions of risk, life style, and late modernity are also discussed. lastly, the multiple dimensions of the idea of the 'relativity' of a risk are considered: this construct is produced within a particular era; it is tied in with a certain view of the world and of human experience, thereby influencing theoretical and methodological approaches.