NGOs play an institutionalised role in the European Union (EU), serving as unofficial opposition in a system otherwise orientated around consensus, and as policy partner to in times of need. Dialogue with institutions is structured along pluralist lines, but with pockets of quasi-corporatist practice, despite rejection of corporatist systems. A mature landscape of NGOs activity exists, with those founded at EU level self-organised into ‘families’ and network structures where professionalised social movement organisations rub shoulders with formal NGOs. Key debates involve the extent to which NGOs are instrumentalised by EU institutions, which stimulate group formation and fund NGOs, and the extent to which input legitimacy can be based around dialogue in the ‘Brussels bubble’. EU institutions have opened up avenues of direct dialogue with citizens in pursuit of systemic input legitimacy, despite aspirations among some leading NGOs for this to be founded upon a ‘civil dialogue’ between themselves and EU institutions.