International law scholarship has not adequately recognised the magnitude of the role of ‘global civil society’ in ‘global governance’ and ‘international lawmaking.’ Building upon theoretical, historical and legal scholarship and presenting studies of GCS actor practice in a wide range of lawmaking processes, including treaty-making, conferences, international organisations and adjudicatory mechanisms, this book convincingly demonstrates that GCS actors have created and influenced the creation of norms of binding public international law and influential non-binding ‘soft’ or non-law. It presents a compelling case that calls for augmenting GCS access to information, participation in legal decision-making processes for those likely to be affected, and access justice thereby enhancing the legitimacy of public international law.