Abstract This chapter argues that one of the main goals of an international rule of law is the protection of state autonomy from arbitrary interference by international institutions and that the best way to codify this protection is through constitutional rules restraining the reach of international law into the internal affairs of a state. State autonomy does not have any intrinsic value or moral status of its own. Its value is derivative, resulting from the role it plays as the most efficient means of protecting autonomy for individuals and groups. Therefore, the goal of protecting state autonomy from the encroachment of international law will have to be constrained by, and balanced against, the more fundamental goal of an international rule of law: the protection of the autonomy of individual persons, best realized through the entrenchment of basic human rights.