Hypertension causes a number of alterations of the coronary circulation which may influence the outcome of anaesthesia and surgery. These include changes in the architecture of the coronary vasculature, and impairments in coronary reserve and autoregulatory ability of the coronary microvasculature during decreases in perfusion pressure. Chronic hypertension may also alter endothelial regulation of vascular control. Many of the vasodilators used to treat hypertension may have unique effects on the coronary circulation which may become modified by chronic hypertension and cardiac hypertrophy. In this review, each of these areas are considered together with some unique aspects of endothelial/vascular smooth muscle interactions as they relate to acute and chronic hypertension, and to the pharmacological agents used in the treatment of hypertension.