Pulmonary hypertension, in its simplest sense, is elevation of the pulmonary artery pressure above normal. A multitude of diseases may increase the pulmonary artery pressure and result in right ventricular dysfunction. The treatments of pulmonary hypertension are as varied as its causes. The past decade has realized remarkable growth in knowledge of the mechanisms of pulmonary arterial hypertension and, concurrently, therapies for this once uniformly fatal disease. In addition to continuous intravenous epoprostenol, subcutaneous treprostinil and oral bosentan are now FDA approved for the treatment of pulmonary arterial hypertension. Other forms of pulmonary hypertension, such as pulmonary venous hypertension, pulmonary hypertension related to diseases of the respiratory system, and thromboembolic pulmonary hypertension will be discussed.