Arterial hypertension is one of the most important modifiable risk factors for cardiovascular disease. Treatment of hypertension has been shown to decrease the risk of myocardial infarction, stroke, congestive heart failure, end-stage renal disease and peripheral vascular disease. It is apparent from some results that blood pressure should be lowered in all patients having other cardiovascular risk factors regardless whether they are hypertensive or non-hypertensive persons. However, complete information considering awareness, treatment and control of arterial hypertension is still missing. The aim of our study is to obtain these data for the entire region of the Republic of Croatia. The study will be finished in two years and new hypertension related cardiovascular risk indicators such as isolated systolic hypertension, pulse pressure and heart rate will be analysed as well. Therapeutic success will be analysed in particular subpopulations considering applied therapy.