The main impetus here has been to point to the necessity of a coherent theory of sources in international law which allows for flexibility, while setting a conceptual framework that explains developments in the social practice of international law. To do this comprehensively, we may have to acknowledge the pluralist—or fragmented, as some may call it—nature of international law: different fields or regimes have developed their own methodology of making law. At the same time, noting that the rule of recognition must be settled to some extent to avoid ambiguous outcomes, I suggest, as other scholars have done before me, some minimal substance to it that then validates norms of law.9 In general, the presupposition in these remarks is that international law has in fact evolved into a legal system consisting of identifiable primary and secondary rules, and a meta-rule—the rule of recognition—even if not yet a fully fledged one.