As the twenty-first century marches on, the global community is confronted with a number of complex issues, including climate change, poverty, epidemics, and terrorism. Despite its imperfections, the United Nations remains the primary international organization for addressing these challenges. The United Nations: Leadership and Challenges in a Global World explores the history, structure, and activities of this most vital institution. The series will help students understand the problems the organization faces—such as international discord and its own complex bureaucracy—as well as the UN's promise of global solidarity and security.