Given the ageing population of occupational health physicians and the deteriorating situation of employee health, reforms targeting the multi-disciplinary nature of occupational health are currently being drawn up. These are of great concern to doctors in terms of the future of occupational health, notably with regard to changing medical practices. The objective of this study is to explore the actual practices of occupational health physicians within the framework of MSD prevention in France. By analysing the activity of occupational health physicians, we could gain a better understanding of the coordination between those involved in OHS with the ultimate goal being to improve prevention. Based on an analysis of peer activity, this method made it possible to push beyond pre-constructed discourse. According to activity theories, it is through others that the history and controversies of a profession can be grasped and skills developed. The results produced by these collective discussions on activity analysis contributed to establish a collective point of view about the important aspects of their profession that need defending and the variations in professional genre in relation to the current reforms, notably.