Succeeding in a military operation requires continuous and comprehensive situational awareness. Early warning is about movements in the air, on land or at sea, to enable our own troops, air and maritime assets to operate effectively in their area of operations. Situational awareness further enables them to prepare and react appropriately to any changes in the operational environment.

NATO operates two units specialized on providing situational awareness for the Alliance in the air, land and maritime domain, operationally controlled by Allied Air Command: NATO's Airborne Early Warning and Control Force as well as the Alliance Ground Surveillance Force.