The United Nations Disaster Assessment and Coordination (UNDAC) is part of the United Nation’s international emergency response system for sudden-onset emergencies.

UNDAC was created in 1993 with the mandate of assessing, coordinating and managing information during emergency response missions. It was designed to help the United Nations and governments of disaster-affected countries during the first phase of a sudden-onset emergency.

UNDAC assists in the coordination of incoming international relief at national level and/or at the site of the emergency. The UN Environment/OCHA Joint Unit (JEU) often deploys environmental expertise through the UNDAC mechanism.