||AbstractIn France, the last decade has been marked by an extensive development of public interventions in the field of mental health. The political investment in mental health has been the object of a public debate in which prevention was perceived by professional opinion leaders as a mean for politics to implement social control policies. However, it seems that the vigor of these condemnations has jeopardized the opportunity to initiate a debate on the ethical, sociological and epistemological foundations of prevention in mental health. Aim and method: EPIONE study was set up to meet the need for psychosocial research to evaluate the social representations of prevention in mental health professionals in charge of prevention, within the French context. Using one open-ended question (?What do you think about prevention in mental health??), representations from 616 professionals were analyzed through a computer-assisted process (Alceste software) and according to Denise Jodelet and Serge Moscovici models of social representations. Results: Results pointed out an important discrepancy between the political discourse and the social representations of professionals, who understand the field of prevention as intimately related to curative practices. Professionals do not seem concerned by preventive ?top-down? policies, which they perceive as technocrats? issues. Finally, only a third of the total responses was related to the criticisms addressed to prevention, suggesting that mistrust toward prevention was not as developed among field professionals as it might seem when reading the most visible critical publications. Conclusion: We suggest that, in order to adapt public health and prevention policies, decision makers will have to rely on professionals? background and on the field reality, as well as the epistemological, sociological and ethical problems raised by public prevention in mental health.