We reviewed 53 cases of synovial chondromatosis and compared their clinical, radiological and pathological features. A radiological diagnosis is possible with increasing frequency as the disease progresses; in the early phase arthrography is helpful. Radiologically the disease may be classified as either extra-articular, or intra-articular; the intra-articular variety may be localised or generalised. Recurrence after operation was seen in 11.5% and was much the same after either synovectomy or simple removal of loose bodies. A protocol for treatment is proposed.