This thesis project regards the development of a four-wheel steering system to improve vehicle handling performance. Introducing 4WS system to a pre-existent multilink suspension of a Maserati sport car, elasto-kinematic performance is virtually analyzed. System control strategy is then designed, combining feedforward and feedback controls to determine rear wheels steering actuation. Simulation experiments of the vehicle assembly provided with the proposed control system is performed. Finally, the dynamic performance of the actuator is introduced into the control system and its impacts are evaluated. Experimental data shows that the proposed four-wheel steering system is able to improve handling performance.