Arterial hypertension, and its most common form of primary hypertension (PH) is the most important potentially reversible cardiovascular risk factor. PH is not a disease of adulthood but it starts to develop already in childhood and in large part is even programmed perinatally. The prevalence of arterial hypertension in childhood is relatively rare and in all pediatric population is about 10 times lower than in adult population. However, in adolescents the prevalence of arterial hypertension is the same as in young adults. PH is not only hemodynamic phenomenon but rather complex immune-metabolic disease associated with altered sympathetic activation. This causes significant challenge both for paediatricians, general physicians and internists.