Long-term-treatment of rheumatoid arthritis (RA) with D-Penicillamine (DPA) is well established. In several controlled clinical studies, DPA-therapy has been shown to be effective, even in lower dosage (450--600 mg/day) than used in first years after introduction of this drug. As the dosage has been reduced there was a marked decrease in unwanted drug effects. Nevertheless proteinuria, agranulocytosis and LED-like syndromes remain serious side-effects. Therefore a close supervision of patients under DPA is still necessary. The limitations for DPA-treatment are age, disease activity and LED-like symptoms. RA-patients with renal insufficiency, penicillin-allergy, hematopoietic dysfunction, cancer and chronic infections should never be treated with DPA.