Legal scholars have observed that there are two types of decisions: the routine decisions that resolve disputes about meum and tuum and constitutive decisions that change the very structure and process of making decisions. Routine decisions may sometimes, often by implication, have constitutive elements. That is certainly the history of the application of Article 52 of the ICSID Convention. Ad hoc Committee after ad hoc Committee has wrestled with the questions of the proper scope for the application of Article 52, its function in the overall ICSID scheme and, indeed, the role it should play in the legal enterprise called international investment law. In this sense, each of the published ad hoc Committee decisions and the cumulative jurisprudence of Article 52 from its first application in the Klöckner v. Cameroon case, together comprise a sequential constitutional debate about the scope and purpose of the function provided for in that provision.