The study of the professional identity which is developed in this thesis addresses the themes of profession, professionalization and professional identity, which are all current issues in the present background of modernization and job mobility. This research is taking place in the the field of French physiotherapy, a profession which has undergone different phases of transformations and identity changes. The other field carried out by this research is fasciatherapy Danis Bois Method, a manual therapy originated in osteopathy which has long been part of the physiotherapy environment. The research question was formulated in order to address this cross section between physiotherapy and fasciatherapy: « How and in what ways do physiotherapists who practice fasciatherapy are led to reconfigure their professional identity? » In view of bringing answers to such questioning, a quantitative survey was conducted using a selfadministered questionnaire on 446 physiotherapists practicing fasciatherapy. This survey brought numerous results and information which allow a better understanding of the identity of the investigated physiotherapists, with regards to their reference profession. It reveals the existence of three identity profiles amongst physiotherapists practicing fasciatherapy, and also documents identity reconfiguring processes depending on the profile. This piece of work forms a scientific basis for further characterization and assessment of fasciatherapy.