Introduction: The health status of Travellers is poorer than that of the general population due to their more precarious living conditions. There are no epidemiological studies on this group in France, which further exacerbates their invisibility in public health programs. Discrimination against them, their mistrust of the government and institutions, and their lack of prioritization of health justified the conduct of participatory research on their health, carried out jointly in Nouvelle-Aquitaine by researchers, policymakers, community organizations, and volunteer Travellers. Study Objective: The objective of this article is to share the challenges, contributions, and issues involved in the co-construction of this research. Results: The approach allowed for the expression and consideration of the specific and sometimes divergent expectations of the stakeholders. It required a period of mutual acculturation, resulting in high participation in the study (74%), the acquisition of new knowledge and skills, and the identification of controversies. This participatory approach fostered greater ownership of the study and heightened awareness of health issues among the respondents, particularly through the co-development of the questionnaire and communication tools. Conclusion: This approach underscores the need to fully integrate stakeholders into the governance of the research project from the outset. This approach was all the more crucial as it involved socially excluded individuals and aimed to avoid further excluding them from the production of knowledge concerning them.