1. A millimeter-wave (MMW) screening system comprising: a first rotatable MMW sensor mounted in a structure and on an axis so as to rotate about the axis, the axis extending along an object viewing region scannable by the sensor; a reflector positioned away from the object viewing region and disposed so as to reflect MMW radiation received from the object viewing region to the sensor; and a display and processing terminal adapted to receive digital data derived from MMW signals from the first rotatable MMW sensor based on data collection from multiple positions of sensor rotation about the object viewing region, and to process said digital data to provide an image of the object viewing region.