This casebook may get more attention today than ever before in its history. From the Russian invasion of Georgia to the on-going detentions at Guantanamo Bay, the use of suicide bombs, to the workings of the United Nations Security Council in a crisis like Darfur, some of the most pressing legal issues of the day are found in this branch of international law. Brings together cases and materials on both the law governing the resort to armed force (jus ad bellum) and the law governing the conduct of force (jus in bello) Provides a dynamic introduction for students, scholars, and practitioners. In addition to adding important new cases from the International Court of Justice, the United States Supreme Court, Israeli High Court of Justice, and others, the second edition adds a completely new chapter on prohibited weapons that begins with nuclear weapons and ends with suicide bombs.