Since 2012, the French agricultural sector is enjoined to move towards Agroecology. Also what Agroecology means is controversial, most of the farmers’ consultancy organizations now recognize that it implies : (i) to deliver a more systemic and strategic advice for farmers; (ii) to become involved in multi-stakeholders settings to foster innovation in agri-food systems or/and to manage natural resources. The Chambres of Agriculture took on board these new challenges: new service packages were proposed to farmers, and consultants were committed to their delivery without a clear-cut definition of the required skills to achieve this. The range of change required to deliver such services being often underestimated, the consultants felt unskilled and lost confidence in their own ability to deliver a relevant advice. In a former study, we proposed a didactic intervention (Cerf et al., 2010) to support consultants in developing new skills at individual and team level. We then proposed to various consultancy organizations to identify some consultants who will, within their own organization, act as a designer and a facilitator of such a didactic intervention within their workplace. In this paper, we will present the main features of a didactic intervention carried on by two consultants who designed it and facilitating the exchanges among their own peers in the Burgundy Region. This intervention took place over three years during two-day meetings, twice a year. Ten advisors, hired by the local Chambres of Agriculture, joined these meetings. First we will explain how the didactic intervention was organized into sequences which purposes were: (i) to challenge the current routines and to support advisors in developing their ability to become transition facilitators; (ii) to give them an opportunity to collectively design the way to perform this new role and discuss their professional norms. Second, we will analyze the discussions which took place during the meetings to point out how the collective explores the coupling between a given consultancy situation and the consultant’s performance in this situation (activity analysis). Third, we will give evidence of the professional development which took place during this didactic intervention, whether at individual or collective level. At individual level, we will show various trajectories of professional development and the place the didactic intervention played in such trajectories. We will show the role played by key resources in supporting the individual and collective professional development : (i) the didactic situations proposed by the facilitators, (ii) the discussions held in the collective to carry on the activity analysis (iii) the support offered by the collective to dare new ways to act. Individual professional development occurs on the long run: it depends upon the room to maneuver given by the organization to the consultant and the ability of the last one to identify them. At collective level, routines are discussed and consultants progressively build together a new job identity. To conclude, we will discuss the relevance of such a didactic intervention at workplace and the new role taken by those who design and facilitate this intervention in their own organization.