Investigates the association of race and rural residence on rates of diagnosis of diabetes and cardiovascular disease and indicators of good medical control among people with diabetes, hypertension, and cardiovascular disease. Finds that rural African Americans with diagnosed diabetes have significantly higher rates of problems associated with diabetes than do urban whites; that rural and urban African Americans are more likely than rural and urban whites to have undiagnosed diabetes; that rural African Americans with diagnosed hypertension are more likely than urban whites to still have elevated diastolic blood pressure; and that rural African Americans have the highest prevalence of undiagnosed diastolic hypertension. The study documents the need to improve access to healthcare services in rural areas.