Ambulatory blood pressure monitoring is an evolving technology. It has an established role in the diagnosis of hypertension, the clinical management of selected patients, and in the evaluation of new medication. From continuous recording much has been learned about the circadian nature of blood pressure and heart rate. Future research holds promise for a greater understanding of the mechanisms and treatment of cardiovascular disease. The purpose of this short review is to describe the development of ambulatory blood pressure monitoring, and outline some of its important contributions to date; and also to explore the research potential and clinical utility of advanced intravascular monitoring techniques, such as the continuous recording of pulmonary artery pressure in ambulant patients.