This contribution investigates the empirical foundation of the claim that civil society participation mitigates the democratic deficit of international governance. In a first step, two potentially democratizing functions of organized civil society are identified: direct channelling of citizens’ interest into international negotiations and a contribution to the emergence of a transnational public sphere. While the creation of public visibility is rather unproblematic direct input into negotiation processes is often hampered by the conditions of executive multilateralism. Moreover, we need to acknowledge trade-offs between constructive collaboration with international organizations and public opposition against their policies.