AbstractInternational law is becoming increasingly more specialized and diversified. In response to these developments, international lawyers now widely refer to international investment law, European human rights law and many other branches as ‘special regimes’. Scholars in the field see the proliferation of special regimes as a threat to the unity of the international legal system. In so doing, they are applying the traditional definition of a special regime as a collection of norms. This article encourages readers to conceive instead of a special regime as a community of practice—as an activity structured around the normative presuppositions of the people and institutions that participate in it. This new understanding, the article argues, is compatible with all predominant theories of law. When you adopt it, importantly, the proliferation of special regimes does not have the disintegrating effect that many scholars believe it to have.