Solidarity is a contested and elusive concept. Nevertheless, it has made a considerable contribution to the shape and character of European Union (EU) integration from pre-European Economic Community (EEC) days to ongoing debates in the Conference on the Future of Europe. Indeed, solidarity has been characterised as ‘both the raison d’être and the objective of the European project’.1 Yet that impact has been achieved despite a less than obvious ‘fit’ between classical notions of solidarity and the complex system that constitutes the EU. Without adopting any essentialist approach to the meaning of solidarity, orthodox expositions emphasise close ties between individuals that involve sharing or redistributing resources, usually carrying connotations of political action and often situated in the social sphere. Put another way, solidarity is frequently understood as an affective condition defending particular values and usually most effective at local levels.