摘要:“State Enforcement in an Interstate World” is an important topic—fully deserving of all the attention it has received. Past commentators on this topic have generally treated the federal government as a unitary entity. Building on prior work on the subject, this Article explores the polycentric nature of federal regulatory authority and shows how cooperation and rivalry have long been dominant realities of the modern administrative state. The Article discusses how these dynamics complicate analysis of state enforcement in an interstate world and identifies strategies for reducing the frequency and magnitude of the seemingly inevitable conflicts.