Abstract: A cruise control system for a vehicle includes a vehicle borne radar for determining range and closing rate of the vehicle relative to a target, such as another moving vehicle, ahead of the vehicle. The range and closing rate are used to determine a new set speed for the cruise control system which may be less than but is not greater than the speed entered in the cruise control by the driver of the vehicle. The new set speed is selected to prevent the vehicle from overtaking the target, and ideally reduces the closing rate to zero at a predetermined minimum distance from the target. In determining the new set speed, the system also determines incremental movements for the vehicle throttle using a selected gain boost and designed to minimize throttle jerk. If the target moves out of the path of the vehicle or speeds up, the system adjusts accordingly and eventually allows the vehicle to resume the originally entered speed when possible.