Abstract
The aim of this article is to describe basic field research (Wisner, 1995; Clot, 2008a, 2008b) as we conceive it in our research programs and as we implement it in schools, with teaching professionals. We present both the epistemological and theoretical orientations and the methodological choices that our transformative and epistemic studies adopt to do basic field research. In this context, the article develops the problematic of the relations between researcher(s) and professional actor(s) by describing the processes for the co-construction of the object of study and the collective elaboration of the transformations of the activity that the self- confrontation interview method helps to bring out during the research. Three studies illustrate this process of fundamental field research conducted with teachers in schools. Using these three studies to discuss the conditions of the development of teacher activity, it becomes possible to underline points of agreement and debate with other studies which claim of basic field research.