As explained in the previous chapters, the determination of the coordinates (positioning) of a point in space is generally based on terrestrial measurements (horizontal directions, vertical angles and distances) carried out using surveying instruments installed on the Earth’s surface and oriented to a frame of control points linked to a predefined local or geodetic reference system. Exceptions to these prerogatives are the determination of coordinates using airborne photogrammetry (Chap. 19 ), airborne laser scanning (Chap. 18 ) and artificial satellite positioning, as discussed in this chapter.