Under this concept, NATO forces should be able to rapidly deploy to crisis areas and remain sustainable, be it within or outside NATO's territory, in support of both Article 5 and Non-Article 5 operations. The successful deployments of the Allied Command Europe Rapid Reaction Corps (ARRC) to two NATO-led Balkan operations (the Implementation Force (IFOR) to Bosnia Herzegovina in 1995 and Kosovo Force (KFOR) to Kosovo in 1999) are early examples of non-Article 5 crisis response operations outside NATO territory.

Article 5 operations commit each NATO member state to consider an armed attack against one state to be an armed attack against all states. Non-Article 5 operations are operations that are not concerned with collective defence.

High Readiness Forces and Forces of Lower Readiness

There are forces of two different kinds of readiness posture; first, forces with a higher state of readiness and availability, the so-called High Readiness Forces (HRF) to react on short notice; second, forces with a lower state of readiness (FLR) to reinforce and sustain. Graduated Readiness Headquarters are being developed to provide these forces with command and control facilities.

High Readiness Forces (Land) Headquarters candidates available:

The Allied Command Europe Rapid Reaction Corps (ARRC) HQ at Innsworth with the United Kingdom as framework nation;

The Rapid Deployable German-Netherlands Corps HQ, based on the 1st German-Netherlands Corps HQ in Munster (Germany);

The Rapid Deployable Italian Corps HQ based on the Italian Rapid Reaction Corps HQ in Solbiate Olona close to Milan (Italy);

The Rapid Deployable Spanish Corps HQ based on the Spanish Corps HQ in Valencia (Spain);

The Rapid Deployable Turkish Corps HQ based on the 3rd Turkish Corps HQ near Istanbul (Turkey);

The Eurocorps HQ in Strasbourg (France) sponsored by Belgium, France, Germany, Luxembourg and Spain.

Note: The Eurocorps Headquarters which has a different international military status based on the Strasbourg Treaty has signed a technical arrangement with SACEUR and can also be committed to NATO missions.

Forces of Lower Readiness (Land) Headquarters candidates:

The Multinational Corps HQ North-East in Szczecin (Poland) sponsored by Denmark, Germany and Poland;

The Greek C Corps HQ near Thessaloniki (Greece).

High Readiness Forces (Maritime) Headquarters:

Headquarters Commander Italian Maritime Forces on board of the Italian Naval Vessel GARIBALDI

Headquarters Commander Spanish Maritime Forces (HQ COMSPMARFOR) on board of LPD CASTILLA

Headquarters Commander United Kingdom Maritime Forces (HQ COMUKMARFOR) onboard a UK Aircraft Carrier.