People pursuing careers as international lawyers, diplomats, and policy advisors need to know international law. Corporate lawyers, ambassadors, mediators, and legal advisors also use international law. You can apply your knowledge of international law to many different fields of work as well. Understanding the law can help people who are doing international humanitarian work determine how people have been harmed by laws and how laws can help them recover. Workers involved in international relations and diplomacy use international law as a way to understand the opportunities available and limitations involved in relations between countries. People in international business need to know the rules and regulations of the region in which they're operating.