The Supreme Court has never articulated a coherent theoretical justification for the law of personal jurisdiction. While some opinions state that the law is based on state sovereignty, others hold that it is instead derived exclusively from the Due Process Clause’s concern for fairness. None of the opinions, however, clearly ties either of these theories to the blackletter law of personal jurisdiction. This confusion over the purpose of the doctrine has helped to create divisions both within the Court and among the Circuits on a number of important jurisdictional issues. This Article argues that the law of personal jurisdiction must take sovereignty into serious account and provides a new interpretation of how sovereignty should inform the ...