Coexistent diabetes and hypertension affect an estimated 2.5 million persons in the United States. Hypertension occurs approximately twice as frequently in persons with diabetes as without and contributes to most of the chronic complications of diabetes, including coronary artery disease, stroke, lower extremity amputations, renal failure and, perhaps, to diabetic retinopathy and blindness. The proportions of complications in the diabetic population attributable to hypertension range from 35 to 75 percent. Hypertension in the diabetic population increases with age and is particularly associated with obesity and nephropathy. Limited data suggest the control of hypertension in the diabetic population may be better than in the general population, perhaps due to greater contact that persons with diabetes have with the health care system. Yet, in approximately half, hypertension is not controlled. Control strategies for hypertension in the diabetic population must take into account the higher frequency of hypertension, increased risks for adverse sequelae from the coexistent conditions, more complicated clinical management, and the greater contact with the health care system experienced by persons with diabetes. Community programs to improve hypertension control in the diabetic population may target a subset of the diabetic population and should tailor strategies to meet the needs of the target population. Hypertension control in the diabetic population must be addressed at multiple levels in the health care system, including improved detection, evaluation, and treatment of hypertension; improved adherence to antihypertensive therapy and long-term followup; provision of quality professional education and patient education and support; and systematic health care monitoring and program evaluation. Hypertension control should be emphasized in all comprehensive diabetes control programs.The treatment and control of hypertension may significantly reduce morbidity and mortality in the diabetic population.