The diagnosis of arterial hypertension cannot be in doubt with repeated high blood pressure readings (140/90 under 40 years and over 40 years 160/95). In particular it will be easier to reconcile a patient who has no symptoms and who is not motivited by complaints to the understanding of a usually lifelong therapy by an exhaustive discussion. The patient must know that the risk of secondary cardiac diseases increases continuously with the level of the average arterial pressure (both systolic and diastolic) and that this average pressure includes all values of the excessive range of fluctuation of the blood pressure in hypertensive disease (stress peaks, resting values). The diagnostic program leads to a causal (surgical) therapy only in isolated cases (1 to 2%). For symptomatic therapy the general measures "adjustment of the way of living" and "diet" are the decisive basis for effective treatment.