In this article, Gostin and Archer explore the varied lenses through which governments are obligated to address humanitarian needs. States'responsibilities to help others derive from domestic law, political commitments, ethical values, national interests, and international law. What is needed, however, is clarity and detailed standards so that States can operationalize this responsibility, making it real for developing countries. Transnational cooperation needs to be more effective and consistent to provide assistance for the world's poorest and least healthy people.