States that interact in the international arena claim authority within their area of jurisdiction; they claim a right to rule and to govern the practical rationality of their subjects. When states are regularly obeyed and subjects acknowledge their authority claim, they have a de facto authority that enables them to control the behaviour of their subjects. The capacity that a political entity has to successfully exercise de facto authority in order to control the behaviour of agents is a valuable asset that is the object of negotiation at the international level. The role of international law is that of harmonizing the exercise of authority of multiple independent political entities in order to enable international cooperation. Authority, however, is not a commodity, but a normative power which is subject to standards of political legitimacy. The international order is an authority-specification system that aims to regulate the future exercise of political power of domestic political entities. The international order must not only preserve the moral significance of collective choices by protecting the right of self-determination of domestic societies: it must also enable societies to interact under conditions that allow international agreements to have a normative weight. An international order is only legitimate if choices about foreign policies can be normatively transfonnative. According to this, consent among international actors must be given under conditions that attribute control over the proceeding to international actors. International relations should be conducted under background conditions of political fairness that enable international actors to have an adequate chance to influence political outcomes. International procedures of negotiation and law-enactment have an independent moral significance and they must justify the limits they aim to impose on domestic sovereignty.