The Incident Command System (ICS) is the foundation for an effective all-risk response capability to any critical incident.  The ICS is the most effective method for managing disasters, in part by economizing resources. Economy of resources requires:

• Establishing goals
• Setting priorities
• Assigning resources

Functions of the ICS may be expanded to meet the needs of each situation regardless of the magnitude of the disaster.

A critical incident is defined as, "Any natural or man-made event, civil disturbance, or any other occurrence of unusual or severe nature that threatens to cause or causes the loss of life or injury to citizens and/or severe damage to property. Critical incidents require extraordinary measures to protect lives, meet human needs, and achieve recovery."