This paper finds that the ICJ's Kosovo Advisory Opinion reached the right result, but in a methodologically not fully satisfactory way. It examines five aspects that underpin the opinion: the temporal (purely ex post) perspective; the Court's equation of legal conformity and non-prohibition and the idea of a deliberate silence of international law; the applicability of the Lotus principle that was evoked by numerous states in the proceedings; the structural analogies between international law and private, criminal, or public law; and the oscillation between legal positivist and jusnaturalist paradigms. Finally, the paper argues in favour of procedural requirements for the international lawfulness of secession, and claims that this approach is compatible with the findings of the Advisory Opinion.
