The angiotensin receptor blockers (ARBs) are well established as safe and effective in the treatment of arterial hypertension. Telmisartan is an ARB with potent blood-pressure lowering effects. It has a long terminal half-life of about 24 hours (the longest of any of the ARBs), which enables it to sustain blood pressure reductions in the early morning hours, after the previous morning dosing. Unlike the angiotensin-converting enzyme (ACE) inhibitors, the ARBs have not been shown to reduce mortality and morbidity in high-risk patients with coronary disease, peripheral vascular disease, cerebrovascular disease, or diabetes with cardiovascular risk factors without evidence of heart failure or low ejection fraction. Two studies, the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) and the Telmisartan Randomized AssessmeNt Study in ACE-I INtolerant Subjects with Cardiovascular Disease (TRANSCEND) trial, are examining the benefits of ARBs alone and in combination with ACE inhibitors in high-risk patients.