Essential hypertension (EH) is the most common type of high blood pressure and is responsible for much death and serious illness, which has been the reason for the huge research effort to determine its causes. However, countless scientific articles still keep proclaiming that "the causes of essential hypertension remain unknown." In view of the number of publications that descend on the hypertension specialist like a waterfall, such proclamations seem to overlook the considerable amount of knowledge that we already have about the etiology of EH. The problem may be a lack of synthesis rather than a lack of information. This book provides a unique synthesis of the pathophysiology of essential hypertension (EH), which is limited through the brain and is critically dependent on both genetic and environmental factors such as stress, high salt intake and obesity. Korner analyses the mechanisms by which the various factors raise blood pressure and the pathophysiology of EH compared with that in renal hypertension and in some of the rat models of genetic hypertension. In some individuals stress-induced vasoconstriction enhances the brain's responsiveness to salt, giving rise to stress-and-salt-related EH. In others, stress-induced EH promotes eating, causing hypertensive obesity. Improving lifestyle through regular exercise and reduction of salt and calorie intake directly antagonises the environmental causes of EH, and has implications for prevenion and treatment.