Pulmonary hypertension scares us, and for good reason. Pulmonary hypertension may be caused by an intrinsic pulmonary vasculopathy — termed pulmonary arterial hypertension — or it may complicate other, more common problems such as interstitial lung disease, in which it signals the presence of advanced, often end-stage disease.1 Regardless of its cause, without effective therapy, pulmonary hypertension is associated with worsened dyspnea, mobility, quality of life, and short-term survival. Fortunately, remarkable progress in drug development has transformed a diagnosis of pulmonary arterial hypertension from a disease that is uniformly and rapidly fatal into one that in some patients may be . . .