Focusing on the Change Process: The Contribution of Systemic Intervention to Improve Wellbeing at Work. In the context of an increasing number of interventions on occupational health and wellbeing, it is common practice to use diagnostic-centered methods where an in-depth understanding of the situation precedes the action. However, some authors highlight the practical limits of these approaches and emphasize their difficulties in bringing about change in the workplace on the basis of the diagnosis. By contrast, systemic interventions concentrate on the change process to enable its efficient and sustained implementation, rather than on the reasons for change. In this perspective, this article aims to examine workplace interventions targeting wellbeing, in the light of systemic thinking. To this end, the article presents a brief review of systemic framework and principles, as well as the related intervention methods. The second part of the article highlights how this approach can contribute to the improvement of occupational health and wellbeing. Finally, we use a case study from the service sector to outline the capacity of those principles to focus on initiatives leading to change, in a context of prevention.