Why do international organizations (IOs) exist? Do they shape outcomes in international politics? Who runs international organizations? This course considers the role that institutions have played in addressing global problems since World War II. Some argue their role is trivial, since there is no international police force that can constrain states' behaviors. Others argue their role is profound, as institutions help states to overcome important barriers to cooperation. And just as in domestic institutions, the rules of IOs represent some interests more than others, creating opportunities for controversy and contestation. We will apply these theories to understand several institutions governing economic stability, environmental sustainability, human rights, security affairs, and global development. At the conclusion of the course, students will be able to explain why these IOs exist, how well they work, and what challenges they face in the future.