• pulmonary hypertension
• primary pulmonary hypertension
• persistent pulmonary hypertension of the newborn
• pulmonary vascular obstructive disease
• nitric oxide

Severe, sustained pulmonary hypertension leads to pulmonary vascular obstructive disease, which is potentially fatal. But recent advances in genetics and cell biology provide insights into the pathogenesis of this disease and new treatments offer an improved quality of life and increased survival. The field is moving rapidly, and it is time to adopt a more positive and aggressive approach to the management of pulmonary hypertension in children. The sustained clinical and haemodynamic improvement seen in many adults with primary pulmonary hypertension treated with continuous prostacyclin, and data from numerous experimental studies indicate that it is possible to arrest and perhaps even reverse the disease process. Potential is likely to be greater in the young in whom the vasculature is still remodelling. However, pulmonary hypertension is frequently unrecognised in early childhood and most children are referred late in the course of the disease, emphasising the need to increase awareness of the condition. This review focuses on the more common forms of pulmonary arterial hypertension in the young— persistent pulmonary hypertension of the newborn (PPHN), primary pulmonary hypertension (PPH), and pulmonary hypertension associated with congenital heart disease. It attempts to represent our current understanding of pulmonary hypertension in childhood, highlighting the key features of the condition, and offers a glimpse into the future.