This study examines the question of whether and to what extent the international investment law-making of the European Union integrates sustainable development. The study focuses on international investment agreements concluded by the European Union and compares the European Union's approaches to those of other international actors. The study critically assesses the European Union as a global actor, specifically questioning whether the European Union is proposing new ways to integrate sustainable development or whether the European Union is sticking to the traditional modes of international investment law-making. The results of the study show that the European Union suggests a number of innovative approaches but also that greater development of the law is needed to further transform the regulation of foreign investment in order to ensure that investment activities are environmentally friendly and have real spill-over effects for social and economic development.