This book conceptualizes the World Bank Inspection Panel as a mechanism of quasi-judicial review or oversight, aimed at enhancing the accountability and legitimacy of the World Bank, which is conceived as an international institution exercising public power. The author engages in comparative constitutional law analysis, looking towards three non-international constitutional systems - the United States, the European Union, and post-Apartheid South Africa - to construct a conceptual model of judicial oversight that reflects the concept's nature, effect, and dynamics. The author employs this model to analyze the institutional history and practice of the World Bank Inspection Panel, covering the Panel's entire institutional lifespan. The author concludes that the nature, effect, and dynamics of judicial oversight - indeed, the "judicial spirit" - is more alive in this area of public international law than what might be expected. This book will be of interest to both constitutional and international lawyers, as well as legal practitioners and members of international civil society frequently engaging with international financial institutions such as the World Bank.