The introduction of new surgical techniques in the treatment of cartilaginous injuries has created hope for progress in the treatment of these challenging injuries. However, the results from these interventions vary according to the degree of arthritic changes within the joint, the type of postoperative rehabilitation program, and the length of follow-up. In this article, the scientific background concerning classification and repair techniques for cartilage injuries is reviewed. Also outlined are the clinical results reported to date. Anatomic location, size, depth, consistency, gross appearance, and whether the lesion is in a weight-bearing or non-weight-bearing area should be taken into account when performing an arthro-scopic diagnosis of cartilage injury. Radiographic analysis and magnetic resonance imaging will often be helpful in ruling out commonly associated joint injuries. The use of such new therapies as mosaic arthroplasty and autologous chondrocyte implantation has not been proved superior to the bone marrow-based techniques of microfracture or debridement of the lesion. Postoperative rehabilitation, including weight-bearing status and prevention of muscle atrophy, are considered just as important in achieving successful results. The long-term outcomes of operative repair of cartilaginous injuries in the prevention of joint degeneration is currently unknown and will rely on further progress in basic science and clinical orthopedic research.