The book systematically describes the theory and practice of ICSID annulment proceedings by thoroughly analysing this mechanism in light of the annulment decisions rendered so far as well as the publications on the issue. Organised to suit the needs of the practitioner, it outlines the recent trends in the area, providing the most up to date analysis of the subject. It also addresses key topics involving ICSID annulment such as the procedural issues which frequently arise in this type of proceedings, for example admissability of new evidence and arguments in annulment proceedings, res judicata in resubmitted cases. The sections on each ground for annulment include an analysis of the applicable standard as well as a detailed description and study of each annulment decision that addressed the respective ground, creating an authoritative and complete resource.