A backstepping controller is designed for lateral guidance of the passenger car in automated highway systems. In this design, the vehicle lateral tracking error is viewed as the output regulated by the relative yaw angle of the car with respect to the road centerline, and the relative yaw angle is controlled by the vehicle’s front wheel steering angle. The closed loop performance of lateral and yaw dynamics can be specified and guaranteed simultaneously in this approach. A smooth road model is used in calculating the feedforward part of the steering command. Nonlinear position feedback, which acts as low gain control at small tracking errors and high gain control at larger tracking errors, is introduced to compromise between passenger ride comfort and tracking accuracy. Simulation results conducted on the complex vehicle model show the effectiveness of the backstepping design approach.