OBJECTIVE: To review data concerning combined angiotensin-converting enzyme (ACE) inhibitor and angiotensin II receptor blocker (ARB) therapy for hypertension. DATA SOURCES: MEDLINE (1966–April 2003), IPA (1970–April 2003), and EMBASE (1974–April 2003) with search terms of ACE inhibitor, angiotensin receptor blocker, essential hypertension, and combination therapy. DATA SYNTHESIS: ACE inhibitors provide incomplete blockade of the renin–angiotensin system, sometimes leading to loss of blood pressure control. Addition of ARBs may in theory further reduce blood pressure. Studies of combined ACE inhibitor and ARB therapy for managing hypertension were evaluated. CONCLUSIONS: While studies have shown statistically significant blood pressure reductions with ACE/ARB combination therapy, clinical significance is lacking. Further trials are needed before routine use of the combination can be recommended.