The author analyzes the development of the law of international organizations through the case-law of the World Court and doctrinal writings, and distinguishes three stages. In the first stage (roughly, the interbellum), the law was mainly concerned with trying to come to terms with the new phenomenon of international organizations. In the second stage (peaking in the 1950s and 1960s), the law was predominantly concerned with solving practical problems. In the present third stage, however, conscious attempts are being made to conceptualize and to place organizations in a larger normative perspective. The author concludes that this is a felicitous development.