Recorded mortality from hypertension and stroke has decreased dramatically in most countries during the last 50 to 75 years. The reported reduction in mortality may be due to changes in diagnostic fashions or coding procedures. However, the magnitude and consistency of the decline suggests the occurrence of a true decrease. The possibility that better treatment of hypertension is responsible for the reduction in mortality is attractive. However, based on temporal relationships, it seems more likely that much of the fall has resulted from an alteration in the determinants of blood pressure. Increasing use of antihypertensive drug therapy may account for an acceleration in the decline of stroke mortality during the last decade. If so, this represents one of the first tangible benefits of the massive public health efforts to detect and treat hypertension in the community.