This article analyses the characteristics of the Commission on the Limits of the Continental Shelf as an international decision-making institution in the process of establishing the seaward limits of the continental shelf beyond 200 nautical miles from the baselines of the territorial sea under Article 76 of the 1982 UN Convention on the Law of the Sea. The Commission may be compared to scientific bodies established to give advice relating to the implementation of treaty provisions. However, in the exercise of its functions, the Commission also performs legal-administrative tasks, and its recommendations to individual coastal states entail significant legal effects; for instance, as a means of interpretation under the Vienna Convention on the Law of Treaties. The Commission’s functions and competencies must be taken into account in classifying and understanding this unique international institution.