The authors report the clinical case of a 59 year-old woman who was incidentally diagnosed as having arteriovenous pulmonary malformation (AVPM). Through clinical history a diagnosis of Rendu-Osler-Weber disease (ROWD) was made, a disease manifesting itself through the existence of vascular malformations in the skin, mucosae and viscera (like the lungs, liver and brain). The surgical therapy offered to the patient had no complications. The essential aspects of pathofisiology, clinical manifestations and treatment of AVPM and ROWD are discussed.