An increasing number of medical services dedicated to the diagnosis, treatment and follow-up of pulmonary hypertension (PH) in children are being established. This has, in turn, increased the need to adapt current guidelines for the treatment of PH to be more relevant to paediatric patients with PH. This article will summarise the data obtained so far from paediatric registries, national cohorts and clinical trials and discuss the best approach for developing a treatment algorithm designed for children with different types of PH. The many unanswered questions, challenges and issues relating to the PH in the paediatric population will also be discussed.