Pulmonary arterial hypertension is a life threatening complication of several connective tissue diseases including scleroderma (both diffuse and limited scleroderma, or the CREST syndrome - calcinosis cutis, Raynaud's phenomenon, esophageal dysfunction, sclerodactyly, and telangectasia), systemic lupus erythomatosis (SLE), mixed connective tissue disease (MCTD), and less commonly, rheumatoid arthritis (RA) and dermatomyositis/polymyositis. This report reviews the occurrence of this complication, potential etiologies, clinical presentation, and treatment options. Copyright 2002, Elsevier Science (USA). All rights reserved.