A series of 19 patients with severe rheumatoid arthritis had replacement of both hips and both knees. They are reviewed after a mean follow-up of 27 months. The preferred programme is to replace hips before knees. Pain was relieved in all the patients and function was improved in all but two. Severe rheumatoid disease and prolonged immobilisation before the operations were not contra-indications to a successful outcome, but the presence or the development of cervical myelopathy combined with gross upper limb deformity militated against a good result.