Pulmonary arterial hypertension (PAH) is a rare condition; yet this very rarity can be a disadvantage when it comes to treatment, making PAH difficult to diagnose, and resulting in suboptimal patient care. Furthermore, the global burden of PAH remains poorly understood and largely underestimated, as PAH commonly presents as a comorbidity with such conditions as systemic sclerosis, COPD, idiopathic pulmonary fibrosis and left-heart dysfunction. However, in recent years there has been significant investment in developing new therapies for PAH, and treatment for this previously neglected disease is set to enter a new era. This new work draws on the recent published literature and clinical trials to review the latest developments in our understanding of the disease, new advances in therapy and current opinion on best practice approaches to management. Internationally-recognised authorities on PAH provide expert analysis of these advances and critical commentary on the data presented to help explain the implications of these findings for future clinical practice.