Every-day relations between dwellers of a working-class area and administrations. Understanding the practical bases of representations of public institutions.<br />Based on a fieldwork in a working class area near Paris, this paper shows that the use of the french notion of « service public » is rare among the dwellers. Most use other categories about the « administrations », which are based on practical experiences. Every day relations with some services, such as services of the Council, create ambivalent relations : those relations sometimes lead to criticisms, but also to an attachment to this institution and its agents. More generally, the text shows that the main oppostion that structures jugements about public institutions is the diff...