The factors associated with mortality were examined in a prospective longitudinal study, over an average of 12 years, with 94% followup of patients diagnosed as having rheumatoid arthritis. Of 805 patients, 233 died during the period of the study. Survivorship of rheumatoid arthritis patients was approximately 50% less than that of population controls. Survivorship was decreased by the traditional demographic variables of greater age and male sex; however, a significant independent effect of variables reflecting disease severity (American Rheumatism Association functional class, rheumatoid factor titer, number of involved joints) was identified by multivariate analysis. Seventy-nine excess deaths (i.e., those that would not have been expected in a control population) were due in part to disease-related causes, to infections, and to gastrointestinal complications of therapy. Treatment with gold or prednisone did not seem to affect survivorship or cause of death, except for the clustering of deaths of patients with vasculitis within the prednisone group. Our findings indicate that rheumatoid arthritis, a chronic disabling disease, is also associated with a major decrease in survivorship.