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Incident Command System (ICS)

Why is ICS needed?

When an incident requires response from multiple local emergency management and response agencies, effective cross-jurisdictional coordination using common processes and systems is critical. The Incident Command System (ICS) provides a flexible, yet standardized core mechanism for coordinated and collaborative incident management, whether for incidents where additional resources are required or are provided from different organizations within a single jurisdiction or outside the jurisdiction, or for complex incidents with national implications.

What is ICS Designed To Do?

The ICS is a widely applicable management system designed to enable effective, efficient incident management by integrating a combination of facilities, equipment, personnel, procedures, and communications operating within a common organizational structure. ICS is a fundamental form of management established in a standard format, with the purpose of enabling incident managers to identify the key concerns associated with the incident—often under urgent conditions—without sacrificing attention to any component of the command system. It represents organizational "best practices" and, as an element of the Command and Management Component of NIMS, has become the standard for emergency management across the country. Designers of the system recognized early that ICS must be interdisciplinary and organizationally flexible to meet the following management challenges:

  • Meet the needs of incidents of any kind or size.
  • Allow personnel from a variety of agencies to meld rapidly into a common management structure.
  • Provide logistical and administrative support to operational staff.
  • Be cost effective by avoiding duplication of efforts.

ICS consists of procedures for controlling personnel, facilities, equipment, and communications. It is a system designed to be used or applied from the time an incident occurs until the requirement for management and operations no longer exists.

How does an EOC relate to MACS?

MACS is designed to facilitate the process of multiagency coordination, which allows all levels of government and all disciplines to work together more efficiently and effectively. Multiagency coordination can and does occur on a regular basis whenever personnel from different agencies interact in such activities as preparedness, prevention, response, recovery, and mitigation. More specifically, the primary function of MACS is to coordinate activities above the field level and to prioritize the incident demands for critical or competing resources, thereby assisting the coordination of the operations in the field. MACS consists of a combination of elements: personnel, procedures, protocols, business practices, and communications integrated into a common system.

Emergency Operations Centers (EOCs) are one of several system elements included within the Multiagency Coordination System (MACS). EOCs are intended to facilitate MACS functions, and may provide support to Area Command, Incident Command, or Unified Command when resource needs exceed local capabilities.

What is the relationship between an Incident Command Post and an EOC/MAC Group?

The Incident Command Post is a physical location that administers the on-scene incident command and the other major incident management functions. An EOC is a physical location that is located separately from the on-scene Incident Command Post and supports the on-scene response by providing external coordination and securing of additional resources. A MAC Group does not have any direct incident command involvement and will often be located some distance from the incident site(s). EOC/MAC Groups do not command the on-scene level of the incident, but rather supports the Incident Command Post’s command and management efforts.

All Federal, State, territorial, tribal, private sector and nongovernmental personnel at the following levels of responsibility in emergency management operations – first-line supervisor (Sergeant/Lieutenant), mid-level management (Captain/Shift Commander) and command (Battalion Chief/Division Chief/ District Commander/PIO) and general staff (Operations/Planning/Logistics/Finance-Admin).

To obtain the IS-100 course materials or take the course online go to

The course is designed to be taken online or course materials may be downloaded and used in a group or classroom setting. Approved IS-100 level training may be developed and conducted by Federal, State, tribal, and local agencies as well as private training vendors however it must include the following topics and objectives.

  • Purpose of ICS: Identify requirements to use ICS, three purposes of ICS and common incident tasks.
  • Basic Features of ICS: Describe the basic features of ICS.
  • Incident Commander and Command Staff Functions: Describe the role and function of the Incident Commander and Command Staff.
  • General Staff Functions: Describe the role and function of the Operations, Planning, Logistics and Finance/Administration sections.
  • Facilities: Describe the six basic ICS facilities, identify facilities that may be located together, and identify facility map symbols.
  • Common Responsibilities: Describe common mobilization responsibilities and common responsibilities at an incident, list individual accountability responsibilities, and describe common demobilization responsibilities.

From: Ready.Gov