Over the past ten years, the Comparative Orthopaedic Research Laboratory has studied the use of allograft neocartilage for the resurfacing of joints with either partial thickness or full thickness cartilage defects. The majority of these efforts have focused on a sheep model whereby either partial thickness defects or full thickness defects are created and then transplanted with allograft neocartilage. To date, short and intermediate term studies appear promising and longer-term studies are being conducted.