Since its launch on February 22nd, 1986, the French earth observation satellite SPOT-1, revolving around the Globe on a heliosynchronous orbit at an altitude of 832 km, has returned over a million 60 X 60 km images with 10 m ground resolution in the Panchromatic mode and 20 m in the Multispectral mode. Among the numerous applications of these observations in such diverse fields as cartography, agriculture, environmental studies, oil and mineral exploration, the use of SPOT imagery for National Defence requirements is increasing, both in France and in many other countries. The capacity to acquire data from all over the globe, and the precision of SPOT panchromatic images, superior to that of other civil observation satellites, are fully exploited for this use. Furthermore, the capacity to obtain stereopairs gives access to terrain relief, and introduces the possibility of producing particularly interesting flight simulations. These different applications in the Defence field are well-adapted to strategic needs and will be illustrated in the presentation by a number of examples. Beyond SPOT-1, the satellites SPOT-2, 3 and 4 will ensure service continuity for the international user community until at least 1998, a service continuity unequalled by any other observation satellite programme.