Pulmonary hypertension represents an increasingly important group of pediatric patients which commonly come to the attention, if not the primary care of pediatric pulmonologists around the world. There have been major advances in diagnosis and therapy over the past 25 years. To address potential gaps in knowledge, the authors were invited by the Editor of Pediatric Pulmonology to organize a series of manuscripts in a special supplement of the journal. Our authors include pulmonologists, pharmacists, intensivists, mid-level practitioners, neonatologists and cardiologists. We believe that this issue will be of great interest to most of the readership community that the Journal addresses.