Hypertension and diabetes mellitus are significant and independent risk factors for cardiovascular disease. Antihypertensive therapy reduces cerebrovascular and cardiovascular morbidity and mortality in patients with hypertension. Tight blood pressure (BP) control [target diastolic BP (DBP) less than or equal to 80mm Hg] reduced the incidence of major cardiovascular events by 51% compared with less tight control (DBP less than or equal to 90mm Hg) in patients with diabetes mellitus in the Hypertension Optimal Treatment (HOT) study, Similarly, in the UK Prospective Diabetes Study (UKPDS), tight BP control [mean systolic BP (SBP)/DBP = 144/82mm Hg] with captopril or atenolol reduced diabetes mellitus-related morbidity and mortality by 24% compared with less tight control (mean SBP/DBP = 154/87mm Hg), Importantly, the frequency of microvascular disease (including retinopathy) was reduced by 37% among those randomised to tight BP control in the UKPDS. In the diabetic subgroup in the Heart Outcomes Prevention Evaluation (HOPE) study, there was a 25% reduction in the composite end-point of death due to cardiovascular causes, or myocardial infarction or stroke during 5 years of treatment with ramipril 10 mg/day relative to placebo. Lisinopril is an ACE inhibitor indicated for use in hypertension, heart failure and post-myocardial infarction. As an antihypertensive agent the drug is effective and generally well tolerated in patients with type 1 or 2 diabetes mellitus and in those with early or overt nephropathy. In the Swedish Treatment of Old People (STOP) Hypertension 2 trial, there was no difference in the relative risk of cardiovascular death between those assigned to ACE inhibitors (lisinopril or enalapril), calcium channel blockers (felodipine or isradipine) or 'conventional' antihypertensive therapy (thiazide diuretics or beta blockers); treatment effects did not differ significantly between diabetic and nondiabetic patients (10.9% of the 6614 patients had diabetes mel litus). Importantly, lower frequencies of nonfatal or fatal myocardial infarction [relative risk (RR) 0.77; 95% confidence interval (CI) 0.61 to 0.96] and congestive heart failure (RR 0.78; CI 0.83 to 0.97) were detected during 4 years' treatment with lisinopril or enalapril than felodipine or isradipine in this study. Lisinopril reduced albumin excretion rates in patients with type 1 or 2 diabetes mellitus. In the 2-year EURODIAB Controlled Trial of Lisinopril in IDDM (EUCLID) study, albumin excretion rates decreased by 49.7% relative to placebo in normotensive patients with type 1 diabetes mellitus and microalbuminuria during treatment with lisinopril 10 to 20 mg/day, Progression of retinopathy was attenuated in normotensive patients with type 1 diabetes mellitus during treatment with lisinopril in this study. In conclusion, lisinopril, like other ACE inhibitors should be considered a first-line agent fur reducing BP and attenuating nephropathy in patients with type 1 or 2 diabetes mellitus.