This article studies the design and implementation of an action research project, with eight French colleges of varying sorts, aimed at developing among the various members of the educational community competences to self-assess their establishment and self-regulate their professional practices. By fostering new forms of professional cooperation among categories, the device, presented by a team of four researchers, aimed to increase the individual and collective power to act of those involved, emancipating them from an established hierarchical culture. After presenting the theoretical and methodological framework for this action research, this contribution analyzes the cooperative processes generated by experimentation and the progressive modification of the interveners’ roles.