Pulmonary hypertension (PH) in children is a severe condition. Data describing pediatric PH are scarce. PH, long considered exceptional, is poorly understood.In children, in the majority of cases, PH is secondary to congenital or idiopathic heart disease. The prognosis depends largely on its etiology. Combinations of specific treatments for PH may have contributed to the stability of the disease and better survival.Advances in pathophysiological understanding are opening new therapeutic avenues. A better knowledge of the disease and its epidemiology as well as the organization of care will facilitate earlier treatment, convince the authorities and the industry of the need to make available essential drugs for etiological purposes and rapidly contribute to the improvement of the prognosis of patients.