Thirty-five children who had rheumatoid arthritis were followed for three to twenty-two years. Four categories of involvement of the hip were seen. In the first group, thirteen patients had mild disability and slight radiographic changes. In six of those patients the disease was in remission at the time of writing, and the patients were asymptomatic. In the second group, two patients had episodic disability that correlated with the activity of the disease. In the third group, fourteen patients had progressive disability and radiographic changes. Fifty-five of the fifty-nine procedures that were performed on the hip and knee in this series were done on those fourteen patients. In the fourth group, six patients had dramatic clinical and radiographic findings but, at the time of the latest follow-up, had little functional disability. In all six of these patients, the disease was in remission. In the children in this study, protrusio acetabuli was more cephalad than has been found in adults who have rheumatoid arthritis. All of the children had psychosocial problems, but they responded well to counseling. These problems influenced the timing of the surgical treatment.