The choices that parents make regarding schools are closely associated with educational segregation. On the basis of studies conducted in Rueil-Malmaison, Nanterre, Vincennes and Montreuil, this article analyzes the mental and practical operations that lead parents to construe some social groups as “different” from them. By relating this conception with argumentations, views and values regarding the schooling of their children, these operations are the main cause for the efforts to avoid specific schools. At the same time, the article explores similar operations that lead to construing other groups as “close” or “akin”, and to seeing them as social resources that, by providing judgments, information and practical means, facilitate the devising of strategies.