From an ethnographical research on the place of children’s play within the framework of a leisure center, this contribution wishes to question more widely the function of sociocultural community developer and its professionalization. Starting from the observation and the analysis of situations where children’s play and sociocultural community developer’s recreational activities crisscross, not without difficulties, it will be a question of looking for the playful skill of the sociocultural community developer. However, the learning of this singular skill confronts with the process of rationalization of relational jobs, in particular those of social work and sociocultural community development. Through the notion of project and the risks of the technicization of the practices, we shall approach the return of the sensitive part of the act on the sociocultural community development practices resting on the last researches based on the analysis of the activity.