Résumé
The research we are reporting on in this paper was carried out jointly by researchers in didactics and a specialist in the analysis of the activity. The subject of the research is about studying two collaborative works having worked over several years in which researchers in didactics accompany a group of teachers. The research focuses on how researchers are accompanying the teachers and on the effects of this collaborative work in terms of the professional development of teachers. We crossed the didactic point of view and the point of view of the analysis of the activity via interviews using the past activity traces. The research has made it possible to identify the need for a process of joint problematization and traces of professional development. It also showed the interest of this crossing of viewpoints to study professional development in collaborative work.