Two questionnaires were developed for measuring disability due to juvenile rheumatoid arthritis (JRA), one based on patient reports and one on parent reports. These questionnaires were termed the Juvenile Arthritis Functional Assessment Report for Children (JAFAR-C) and for Parents (JAFAR-P). The questionnaires were administered to 72 JRA patients ages 7-18 years and to their parents. Respondents rated the patient's recent ability to perform 23 activities. Patient reports and parent reports were found to correlate highly with each other and with an objective assessment performed by therapists. Questionnaire scores did not correlate significantly with the age of the patient. The JAFAR appears to be a convenient, reliable, and valid measure of disability in patients with JRA.