Operating principles of three-dimensional (3D) imaging sensors are discussed and various sensor implementation techniques are reviewed. A synopsis of the relative merits of 3D imaging sensors with respect to that of other imaging sensor types is presented. An implementation technique which uses a modulated CW laser source and which has resolution versatility is described and used to illustrate applications diversity. Resulting imagery from laboratory and field measurements provides x,y,z resolution varying from 0.3 m to 0.05 mm. Illustrations presented include: (1) a system for robotic guidance for parts acquisition and inspection; (2) imagery from the 3D vision sensor utilized on the DARPA Autonomous Land Vehicle (ALV); and (3) the 3D vision sensor used on the DARPA Adaptive Suspension Vehicle (ASV). In each application, the 3D features utilized and the resulting data processing are discussed.