In a study of 92 patients with rheumatoid arthritis, we examined patients' beliefs about the causes of their illness, disease flares, and disease remissions, and about the selective incidence of the disease. Numerous self-report measures were used to elucidate the patients' attitudes and perceptions; the tendency of patients to present themselves in socially desirable ways was taken into account and was found not to influence the study results. The causes for the illness that were most frequently cited by patients were heredity (34.7%), autoimmune factor (24.4%), personal behaviors (22.8%), and psychological stress (22.8%). Patients who were more actively searching for the causes of the illness and who continued to ask "Why me?" reported greater functional problems and a greater sense of helplessness. The most frequently cited causes for symptom flares were psychological stress (45.5%), changes in weather (34.0%), and excessive physical activity (34.1%). Symptom remissions were most frequently believed to be related to medication changes (49.4%) and the absence of psychological stress (21.0%). Several of these causal beliefs were related to perceptions of helplessness and the illness' predictability and to health care providers' assessments of disease severity and patients' psychosocial adjustment.