This chapter explains the rise and evolution of environmental regulatory institutions for mining in Peru. The collected evidence shows that without the forging of bureaucratic autonomy, formal rules do not become “institutions” as defined by the canonical work of Douglass North. The forging of bureaucratic autonomy is a self-reinforcing process in which the activism of institutional entrepreneurs within specific organizations and crosscutting epistemic networks, and at particular junctures and contingencies, matters for the chances of the state activism that follows. Layer by layer, institutional entrepreneurs build bureaucratic autonomy, translating globalized blueprints and reinventing old state action.