TWENTY-FOUR HOUR BLOOD PRESSURE PARAMETERS: The use of ambulatory blood pressure monitoring techniques has shown clearly that 24-h average blood pressure is more closely related to the end-organ damage of hypertension than isolated office blood pressure readings. It has also provided evidence that the degree of blood pressure variability over a 24-h period may be independently related to the cardiovascular complications of hypertension. However, all the available data on this issue come from cross-sectional studies, and prospective evidence on the actual prognostic value of 24-h blood pressure parameters has only recently been provided for daytime blood pressure variability. There is still no prospective evidence concerning overall 24-h blood pressure variability. ANTIHYPERTENSIVE AGENTS AND BLOOD PRESSURE VARIABILITY: Available antihypertensive agents are unable to effectively buffer blood pressure variability. However, drugs with a long-lasting antihypertensive effect and an optimal trough: peak ratio may at least prevent further iatrogenic increases in the amplitude of blood pressure fluctuations. BEAT-TO-BEAT BLOOD PRESSURE MONITORING: The ability of antihypertensive agents to actually reduce 24-h blood pressure variability needs to be demonstrated in future studies, using beat-to-beat blood pressure monitoring which is now possible by means of non-invasive techniques.