Intraarticular therapy is an established form of therapy in chronic inflammatory joint diseases. Besides the injection of glucocorticoids, radiosynoviorthesis is a frequently used procedure. Intraarticular injected beta-emitting radionuclides are indicated in chronic synovitis with recurrent joint effusions in rheumatoid arthritis, seronegative spondyloarthritis, villonodular synovitis after surgery and for bleeding prophylaxis in haemophilic arthropathy. The value of radiosynoviorthesis in activated osteoarthritis is not yet clarified.