This article evaluates Australia's tax treaty override following the decision of the Full Federal Court of Australia in Lamesa, in which the Court held that Art. 13 (Alienation of property) of the Australia-Netherlands treaty is limited to the direct alienation of real property. The article contends that Australia breached its international law obligations by overriding its tax treaties and discusses, among other things, Australia's treaty network, the rights and obligations imposed by the Vienna Convention on the Law of Treaties, the application Art. 13 in Lamesa, the international law consequences of Australia's treaty override, the interpretation of tax treaties in Australia, and the influence of the OECD Model and the OECD Tax Treaty Override report.