This chapter deals with the EU’s participation in informal international governance fora, as exemplified by the G7, the G20 and the Global Summits. These fora distinguish themselves from international organisations by their lack of a written statute, formal institutions and decisionmaking procedures. The informality leads to low entry barriers for the EU’s participation as an international organisation, as a result of which the EU can play an important role in these fora. The activities of the Member States and the EU need to be coordinated and the EU has to face the challenge of its dual representation in these fora by the presidents of the European Council and of the European Commission. Moreover, informal international governance fora achieve high rates of compliance with policy commitments to which participants in these fora have agreed. This high degree of impact on policy content, combined with a low degree of formality, raises important legitimacy and accountability questions for these fora and for the EU’s participation therein.