This paper proposes a political economy of social conflict, institutionalchange and crises based on the diversity of perceived interests amongsocial groups. The multidimensional conflict includes ideology,institutions, and politics. Social groups may be in a dominant ordominated position in one or the other dimension, and the nature ofsocial conflict reflects the differences in positions of the various socialgroups in these dimensions. Political stability hinges on the existence ofa dominant social bloc, i.e. a social alliance supporting the rulingpolitical actors. The implementation of institutional change by politicalactors is driven by the search for support. Crisis situations correspondto the rupture of the dominant social bloc. Attempts to emerge fromthe crisis with the reconstitution of a dominant social bloc will havemore or less chance of success depending on the possibility offindinga political strategy that can make the expectations of social groups withdifferent perceived interests compatible. Using examples from theFrench and Italian economic and political situations in recent decades,we show how the proposed analytical framework can inform the studyof institutional change in situations of social crisis