The increasing plurality of actors and places in the international "rule" making of international environmental issues has drawn much attention in international legal scholarship. Yet, the question of how "bindingness" is created remains underexplored and current doctrines of sources and law-making have failed to provide appropriate evaluative tools and explanatory frameworks. The aim of this workshop is to generate new insights with respects to the creation of bindingness in international environmental law (with a special focus on climate change). Participants will be expected to shed light on the question of the "who" (the actors) and the "how" (the process), that are question usually obfuscated in the dominant theories and discourses with regard to sources of international law.