Therapy of cartilage damage is a frequent problem, especially in the young and active patient. For the treatment of a cartilage damage we have to consider the size of the defect, age and weight of the patient, meniscal tears, ligament instabilities and varus-/valgus-malalignment. Lavage, shaving and debridement are only sufficient for a short time and have no long term effect. Abrasio and drilling could be useful in eldery people. Microfracturing seems to be an effective alternative for small defects. The restoration of the cartilage surface with the use of autologous chondrocyte transplantation, osteochondral autograft transplantation and posterior condyle transfer seems to be an adequate treatment for younger patients.