The authors present an extremely challenging case of en bloc heart and liver transplantation in a patient with severe heart and liver failure due to failing Fontan circulation. The patient was a 23-year-old woman, born with single ventricle physiology (pulmonary atresia, hypoplastic tricuspid valve and hypoplastic right ventricle). She presented to the authors’ hospital with end stage heart and liver failure due to failing Fontan circulation. Her medical and surgical history was complicated. She had a history of multiple gastrointestinal (GI) bleeds, severe edema, protein losing enteropathy, and ascites due to liver failure.