Abstract: A pan-tilt unit for positioning or aiming a device requiring motion control, such as a videoconferencing or surveillance camera. The pan-tilt unit includes a base, a rotatable pan platform and a rotatable tilt bed for supporting and selectively orienting the device in a desired direction. The pan platform is rotatably supported on the base about a pan axis, and the tilt bed is rotatably supported on the pan platform about a tilt axis that is transverse to the pan axis. A pan motor and a tilt motor drive the pan platform and the tilt bed in response to control signals that may be provided to the unit across a communication network. The motors may be mounted on the unit to remain stationary relative to the base during panning and tilting operations. The motors may be controlled to rotate in opposite directions to maintain the tilt bed at a fixed tilt angle as the pan platform is rotated about the pan axis.