OBJECTIVE: Disease registries are lists of patients with a particular chronic illness, including clinical information, to improve the care of individuals and populations. The objective of this study was to determine the prevalence of disease registries in physician organizations and the extent to which they are used to improve care. DESIGN: A cross-sectional national telephone survey with a response rate of 70%. SETTING: All physician organizations in the United States with 20 physicians or more. PARTICIPANTS: Chief executive officers, presidents, or medical directors of 1040 physician organizations. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Forty-seven percent of organizations reported having a registry for at least 1 chronic illness, with diabetes registries being the most common. Half (51%) of the registries were not linked to clinical data. Organizations with at least 1 registry were more likely to have implemented other chronic care improvements (P < .0001). Factors associated with the presence of registries in physician organizations include external incentives for quality and extent of information technology capabilities. CONCLUSIONS: Disease registries are not utilized by half of physician organizations. This finding is disturbing because registries have the potential to catalyze needed improvement in chronic care management.