The present invention discloses a drive assist system that includes a drive assist means for providing drive assist to a driver (D), and a drive-assist limitation means for limiting the drive assist when the vehicle speed is equal to or at or below a minimum operational threshold speed. The drive assist system further includes a wakefulness level determination means for determining the level of wakefulness of the driver (D). The limitation of the drive assist is relaxed in accordance with the level of wakefulness.