United Nations Disaster Assessment and Coordination
Sudden-onset hazards —such as earthquakes, floods, or cyclones— often generate urgent humanitarian needs. When the scale of impact exceeds national response capacities, governments may request international assistance from around the world.
For affected authorities, coordination of the response can be complicated by disrupted infrastructure, limited resources, and the sheer diversity of national and international organizations involved. Differences in mandates, reporting arrangements, and cultural approaches often add to the challenge, making it essential to deploy additional capacities to establish clear structures and tools for effective collaboration.
Since 1993, the United Nations Disaster Assessment and Coordination system (UNDAC) is a key part of the international response mechanism for sudden-onset emergencies and is designed to support the United Nations and the governments of disaster-affected countries during the first phase of an emergency. OCHA deploys UNDAC expert teams within 48 hours of a request to support the affected governments and the in-country United Nations agencies, funds and programmes.
Outside emergencies, the UNDAC system supports preparedness efforts of national governments and the UN system in-country. This support may include disaster response preparedness missions, assistance with training and exercises, and the provision of specialized advice in emergency management before, during, and after emergencies.
UNDAC’s methodology is captured in the UNDAC Handbook and the On-Site Operations Coordination Centre Guidelines, which serve as global references for emergency coordination, needs assessment and information management in post-disaster settings.
The importance and success of the UNDAC system was recognized in 2002 in the United Nations General Assembly Resolution 57/150 on “Strengthening the effectiveness and coordination of international urban search and rescue assistance”. In 2024, the UNDAC system was honoured with the UN Heroes Award by the UN Foundation for its contributions to international disaster response and coordination.
UNDAC roster members
The UNDAC roster includes more than 300 seasoned civil protection specialists, humanitarian professionals, and technical experts drawn from more than 150 organizations and 60 sponsoring Member States. These experts are organized into specialized pools that cover key areas such as coordination, emergency needs assessment, information management, environmental emergencies, logistics and other critical fields of emergency response.
Members are nominated by their governments or organizations and trained through a structured programme that includes a two-week induction course, refresher courses, and specialized training.
Operational support partners
UNDAC works closely with a number of partner organizations that provide critical services such as logistics support, emergency telecommunications, satellite imagery analysis, mapping, and impact analysis. These partnerships play a vital role in delivering integrated support and fostering an enabling environment for UNDAC teams and humanitarian partners operating in post-disaster settings.
Resources
UNDAC website (Knowledge Base)