Health and safety at work are closely dependent on how work systems are designed. Design is one of the paths for actions in work-related prevention. But conventionally, these two levels do not often coincide in companies. This leads occupational safety and health aspects to be incorporated after the technical choices have been specified (Lamonde, Beaufort and Richard, 2004). Once the technical and technological choices have been defined, any forms of organization (even those that might be desirable and/or desired) are no longer possible to implement. This means that it is necessary to think through simultaneously all the dimensions of any work system: technical, organizational, and user-activity-related. Moreover, current models for design tend to separate design and implementation (Duarte, 2002), whereas a more global approach would tend to promote more efficient prevention (Vilela et al., 2007). In this perspective, prevention and technical system design should be considered as processes whose beneficiaries are the workers, for whom they can offer many resources for action. So, how can we design work systems that offer as broad a range of organizational forms as possible, and that incorporate efficient rooms for maneuver for workers to be “capable subject”? In this text, we develop an important dimension of work systems that we call "technical and organizational plasticity" (Boudra, 2016). "Plasticity", in the sense used by Béguin (2007b), means the property of a system that "leaves the activity sufficient freedom for maneuver to render technical aspects more efficient whilst remaining in good health". Finally, we go back over the lessons that can be learnt for work-related prevention that is "in connection" (Boudra, op.cit.), rooted in an "offensive" vision of the relationships between humans, their work, and their health.