Processes of change in international law are typically portrayed as centered on states. Other actors (international organizations, civil society organizations, expert groups, or scholars) play a role in these processes as supporting characters. Considering the fragmented or even fractured nature of the world, and the growing polarization among states, how can state-focused models explain the significant changes observed in the past two decades? We propose to explain this under-explored dynamism by shifting the focus away from solely state-centric explanations. We introduce a typology for various other roles states play by building on evidence from different issue areas of international law in which important change processes centrally involve non-state actors, with states occupying more limited or even marginal roles. Our account includes five main roles: central ones as drivers and blockers, marginal ones as bystanders, and intermediate ones as catalysts and spoilers.