Calcium channel blockers (CCBs) are widely used agents in the management of a number of cardiovascular indications, including hypertension, angina and supraventricular tachycardias. By inhibiting the movement of calcium into the cytoplasm via transmembrane calcium channels, they reduce vascular and myocardial contractility, and modulate the activity of pacemaker cells. There are important differences between the different types of calcium channel blockers, and a sound understanding of their mechanism of action is required to promote their safe, effective use. This article briefly describes calcium channel pharmacology, the mechanism of action of CCBs and their place in the therapy of cardiovascular disease.