Seven new classes of antihypertensive agents that are currently under development are outlined. Clinical studies of neutral endopeptidase inhibitors and angiotensin II receptor blockers are described. Experimental studies are described involving endothelin inhibitors, and clinical and experimental studies of a new multiple action antihypertensive agent, carvedilol, are presented. Studies demonstrating the efficacy of very low doses of thiazide diuretics added to other antihypertensive agents are described. A meta-analysis that found increased risk of sudden death in hypertensive patients treated with non-potassium-sparing diuretics is reported. The controversy over the use of calcium-channel blockers is reviewed, and current recommendations regarding the use of rapidly-acting nifedipine are given.