HPS is an increasingly recognized clinical entity resulting from intrapulmonary vasodilatation in patients with liver disease and/or portal hypertension. The pathogenesis of alterations in the pulmonary vascular bed in affected patients is poorly understood and the subject of ongoing investigation. The differential diagnosis of pulmonary symptoms and gas-exchange abnormalities in patients with liver disease being evaluated for transplantation is broad and should be focused on differentiating pulmonary causes that significantly increase the risk for transplantation from HPS where transplantation has emerged as a useful treatment. Specific contraindications to transplantation in patients with HPS have not been identified, though unique postoperative complications have been observed and may be treatable during the frequently prolonged resolution of intrapulmonary vasodilatation. The development of a database of information on patients with HPS undergoing transplantation will provide insight into potential contraindications, prognostic features, and postoperative complications unique to these patients.