The United Nations is a vast and complex organization. The UN System is made up of the Secretariat, headquartered in New York, and a wide variety of specialized agencies, funds, departments, commissions and other bodies. WHO (and PAHO in the Americas) is the specialized health agency. View the overarching structure of the United Nations.

The United Nations Office for Disaster Risk Reduction (UNISDR) is a strategic framework, adopted by United Nations Member States in 2000. The objective of the UNISDR is to guide and coordinate the efforts of a wide range of partners to achieve substantive reduction in disaster losses and build resilient nations and communities as an essential condition for sustainable development.