Can international law be a tool for promoting global justice? Or is international law increasingly obsolete in the face of multiple challenges in today’s world? In this class, we will explore these issues looking at diverse and important areas of international law: 1) international human rights law and accountability for mass atrocity; 2) international environmental law and climate justice; 3) the laws of war, especially the decision to go to war and wars of aggression; 4) international trade law, the World Trade Organization (WTO) and tariffs; and 5) international investment law and investor-state dispute settlement (ISDS); and 6) international refugee and migrant law. But if students wish to do a deep dive on any other international law issue, from cybersecurity to outer space law to law of the sea, you can select the topic of your choice for your two low-stakes assignments and your final paper topic. We will begin the course with an overview of international law, international treaties, and international courts such as the International Criminal Court (ICC) and the International Court of Justice (ICJ). We will use a global justice approach to ask and try to explore the goals and impact of international law. A global justice approach stresses fairness, political and economic equality of both opportunity and outcome, and accountability. The central goal of the course is to familiarize students with legal, analytical and policy tools to enable you to think and act critically when drafting, implementing, or responding to policies related to international law. The course uses cases, role-playing, and simulations to help students learn how to work with international law. We use taped short videos on key class concepts and issues or talks by guest speakers that you can watch before class, so we can “flip” the class and open more class time for discussion and group activities.