Pulmonary hypertension (PH) is a fatal disease caused by small pulmonary artery obstruction from vascular proliferation and remodeling. PH is characterized by elevated pulmonary arterial pressure and increased pulmonary vascular resistance, frequently leading to right-sided heart failure and death. The classification of PH has been recently updated to include 5 major categories of the disorder, are as: Group 1, pulmonary arterial hypertension (PAH); Group 2, PH due to left heart disease; Group 3, PH due to lung diseases and/or hypoxia; Group 4, chronic thromboembolic PH (CTEPH); and Group 5, others. Recently, significant progress has been made in the understanding of the pathophysiology, diagnosis and treatment of PH. Regarding the pathophysiology of the disorder, direct evidence for Rho-kinase activation in the pulmonary artery from PAH patients has been provided. Regarding diagnosis, optical coherence tomography is useful as a new differential diagnostic tool for distal type CTEPH vs. PAH. Regarding treatment, in addition to the conventional therapy, several new drugs are under clinical trial, including fasudil (a Rho-kinase inhibitor), riosiguat (a soluble guanylate cyclase activator), and imatinib (a tyrosine kinase inhibitor). In addition, pulmonary angioplasty and intensive immunosuppressive therapy may be effective for CTEPH and connective tissue disease-associated PAH, respectively. We briefly review the recent progress in the management of PH. (Circ J 2011; 75: 1801-1810)