The arthroscopic surgery of articular cartilage of the knee is beside conservative therapy and invasive surgical procedures an important enrichment in treatment of chondromalacia stage II and III. In the Department of Surgery of the Municipal Hospital of Berlin-Weissensee 3250 arthroscopic operations were performed between January 1983 and December 1988. In 227 patients chondromalacia stage II and III was found which had to be treated by arthroscopic surgery. Four different operation methods were used.