Clinical investigation has demonstrated a high degree of success in the treatment of the incapacitated patient with rheumatoid arthritis (Class IV of the American Rheumatism Association functional classification). 1. The study was based on experience at Rancho Los Amigos Hospital in the management of 183 patients admitted during the four years between July 1962 and July 1966 with attention directed primarily to eighty-seven Class-IV patients, ten of whom were discharged early and not actually treated because rehabilitation was not possible. 2. Class IV was appropriately divided into two categories, depending on both the degree of incapacity at the time of admissions (wheel chair or bedridden), and the functional potential of each individual patient (independent ambulation or wheel chair). 3. Sixty-four (83 per cent) of the seventy-seven patients treated in Class IV improved functionally during hospital treatment. 4. Eight (10 per cent) of the seventy-seven patients treated in Class IV had functional relapses following discharge. More realistic functional goals, determined early in the course of hospitalization, might have reduced the number of postdischarge relapses. 5. Of fifty-four patients who were followed adequately for a period of approximately four years, forty (74 per cent) maintained their discharge functional level. 6. Surgical procedures were performed on 73 per cent of all patients treated. In those individuals operated on as part of their over-all treatment, initial improvement occurred in 90 per cent. 7. If functional incapacity is to be avoided, debility, generalized weakness (particularly in the upper extremities), and contractural deformity must be prevented.