Pulmonary arterial hypertension (PAH) contributes significantly to the morbidity and mortality of diverse cardiopulmonary disorders in paediatrics. The treatment of PAH has dramatically changed over the last decade. A better understanding of the pathophysiological mechanisms has lead to the introduction of several new therapies both in the field of idiopathic and familial PAH or PAH associated with underlying conditions (i.e. congenital heart disease, connective tissue disease, HIV) as well as in the field of acute PAH. The endothelial dysfunction, considered a one of the striking problems of this disease, is characterized by a decreased production of vasodilatory-antiproliferative substances (prostacyclins, nitric oxide) and increased production of vasoconstrictive-proliferative substances (endothelin, thromboxanes). It is currently possible to try to palliate to these deficits by administering prostacyclins or nitric oxide, as well as antagonizing the effect of endothelin through endothelin receptor antagonists. These progresses have first appeared in the adult population but have been rapidly applied to the paediatric population. This short review will discuss these new therapeutic approaches and refers to several large reviews recently published for a more comprehensive description.