A design approach is discussed for the structural rehabilitation of concrete lined tunnels. Depending on the severity of damage, and on the causes that produced it, three levels of rehabilitation are illustrated. They range from light repairs of the inner surface of the tunnel to the demolition and reconstruction of large portions of its lining. In the later case, that represents the most significant problem from the engineering point of view, the use of three-dimensional stress analyses is required to evaluate the safety of the demolition/reconstruction process. The effectiveness of the proposed design approach is illustrated through a case history concerning a highway twin-tunnel located within a slope that undergoes a slow time-dependent movement.