SHADO maintains a base on the Moon that provides a first line of defense against the aliens. The base supports space fighter craft armed with nuclear missiles and missile launching tanks as well as other vehicles and ground defenses.

Space Intruder Detector (SID) is a satellite in high orbit above the Earth. The satellite is equipped with an advanced FTL 'radar' (Utronics) and can generally detect alien craft while they are far enough away for SHADO to mobilize its defenses.