The wavelength is long enough to penetrate most man-made materials such as clothing, but short enough to provide the required resolution for detection of objects of interest with moderate size apertures. Millimeter waves are well-suited for concealed object imaging applications. The system design, characterization and measurements are presented and further uses and improvements are suggested. All of the beam steering components are passive and can be designed to operate at any wavelength. The frame rate of the imager is currently limited by the sweep rate of the vector network analyzer which is used to drive the millimeter wave extenders. The active transceiver and heterodyne quadrature detection allow the measurement of the relative phase between two consecutive measurements and the synthesis of the scene’s Doppler signature. The two-dimensional scan is achieved by mapping the millimeter wave spectrum to space using a pair of crossed gratings. We present a two-dimensional, active, millimeter-wave, electronic beam scanner, with Doppler capabilities for stand-off imaging.