The International Court of Justice rendered its judgement on the merits in the case concerning Oil Platforms (Islamic Republic of Iran v. United States of America) on 6 November 2003. This article reviews the judgement, focusing on the Court's substantive legal determinations on the scope of ‘armed attack’ under the right of self-defence. The review further considers the implications of the judgement as regards the role of the Court in the judicial settlement of disputes. It concludes by considering the impact of the judgement on the legal framework for international peace and security as applied in the maritime context.