International audienceThis paper discusses the concepts of practice, organisation and mediation. It’s aim is to revisit their complementarities but also the tensions that arise when this concepts are "thoughts" together. The concept of practice, theoretically richer that the concept of use (B. Miege, 2007), questions in an communicative approach the technical objets as mediators. Mediation is then seen as an articulation between the individual and the collective. Indeed, people always organize their practices and actions in public space by sharing a set of rules and codes (L. Quéré, 1998). For Ch. Le Moënne (2004) the organizational dimension of social practices is maded of permanent tensions between the social norm inherited from the pa...