The ecological, economic and societal context calls for a profound transformation of farmers' work: a professional transition towards sustainable forms of agriculture seems necessary. The farmer himself carries out the majority of the actions on his farm: the "prescription" comes from several interventions of his socio-professional environment. The transition to more sustainable farming systems is manifested in transformations of the work of the farmer, the accompaniers, the researchers, the counselors and teachers in its different dimensions. The TRANSAE project (TRANSformations of Work and Transitions to Agro-Ecology) is conducted according to a community of practices supporting the transformations of these actors' work. Beyond the co-construction of common methods, practices and tools, this research-action project management transforms, by doing, the ways of thinking and practicing agriculture, support, education and training and research. [ABSTRACT FROM AUTHOR]