The rapid emergence of artificial intelligence (“AI”) has sparked a complex regulatory landscape spanning multiple jurisdictions and scales of governance. While much attention focuses on how to regulate AI, a crucial question remains underexamined: Who should regulate AI? A dizzying array of different kinds of government, operating at different scales, have stepped up. The possible regulators range from cities, to subnational provinces (states in the U.S.), to nation-states, and to international organization. This fragmentation raises two critical questions: What characteristics make a particular governance level optimal for AI regulation? And if a plurality of different actors, working at different scales, acts upon this new technology—as surely seems inevitable—how are their dissonant pronouncements to be reconciled? This proposal would bring together an interdisciplinary group of scholars from the University of Chicago and Sciences Po Paris, among other institutions, to analyze the different ways in which the choice of regulatory problem is being solved in different places. We hope to stage not just a public debate, but also to initiate joint scholarship and a longer research program that potentially draws in other institutions in both Europe and Africa on AI regulation.