In order to provide a lane assist system for a motor vehicle including a surround sensor device, which is mounted on the vehicle, for detecting the lane of the vehicle and a warning device to alert the driver in the event of the vehicle threatening to depart the lane which, with the smallest possible disturbance of the passengers, still enables the driver to initiate an intuitive steering response in a danger situation, it is provided to design and set up the warning device in such a way that a vibration, noticeable to the driver, is generated in the driver seat, to the effect that the vibration is noticeable on the side on which a lane departure threatens or actually takes place.