The prevalence of diagnosed diabetes in the United States is 3%; however, diabetes accounts for approximately 15% of total U.S. health-care expenditures. Preventive-care practices (e.g., glycemic control and regular foot and ophthalmic examinations) can reduce the occurrence and progression of diabetic complications. Although managed-care organizations (MCOs) have assessed the use of such practices through chart reviews, telephone surveys of MCO patients with diabetes are a less expensive method for collecting accurate data. The ongoing, state-based Behavioral Risk Factor Surveillance System (BRFSS) telephone survey can be used to assess levels of care provided by MCOs and self-care practices among persons with diabetes in MCO populations. In 1995, a Colorado-based MCO collaborated with the Colorado Diabetes Control Program (CDCP) to use the state-based BRFSS to assess care practices among MCO enrollees. This report presents findings from the CDCP analysis of data on MCO enrollees aged > or = 30 years who had diabetes; the findings indicate that, although approximately three fourths of enrollees reported most preventive-care practices, two thirds had never heard the term hemoglobin "A-one-C," one fourth had not had their feet examined during the preceding year, and nearly one fifth did not receive an annual dilated-eye examination.