The management of pulmonary hypertension has already incorporated the use of multiple therapies into routine practice. Available therapies act principally through vasodilatation of the pulmonary arterial circulation through well-delineated mechanisms, although right ventricular function determines function and prognosis. Therefore, the goal of these therapies is effectively to preserve right ventricular function through reducing right ventricular afterload. The clinical trial experience of combination therapy is limited and the optimal combinations and administration strategies have yet to be clarified.