This special issue of the European Journal of Social Theory addresses the theme of a crisis in European integration, in particular in the context of the crisis of the Eurozone since 2009. The contributions to this issue offer assessments on the nature of this crisis, its extent and implications. It is now generally felt that the current crisis is particularly significant and marks a turning point in the history of European integration as it addresses new divisions, but also as it faces new opportunities in redefining the relationship between state, economy and society.The post-Second World War project of European integration had never been entirely crisis-free, but the present crisis appears to be different from earlier ones. Earlier crisesopposition to the eastern enlargement in 2002, the failed attempt to create a Constitution, the French and Dutch no votes in 2005, growing opposition to the so-called democratic deficit, etc. -did not imperil transnational governance, which always had the poles of deepening and widening to negotiate. There was never a preordained path to what can no longer be called 'a project'. Indeed, the current situation is characterized by the plurality of possible paths. In the past, the critical issues were largely concerned with the problem of democratic legitimacy while today other issues have come to the fore. The formative period of European integration until the mid-1980s was largely an interstate attempt to achieve market integration through the removal of obstacles to the mobility of capital, labour, services and goods. Normative goals were secondary since the legacy of the Second World War and the aim to bring about lasting peace in the wartorn continent provided the requisite legitimation for a regime that apparently required otherwise only legality. In the early decades, European integration was largely a project of the transnationalization of the nation-state until the point that an optimal degree of