About 10% of children with CF develop hepatic cirrhosis and progressive portal hypertension. As the portal hypertension worsens these children are likely to develop serious variceal bleeding and other complications including malnutrition and a decline in respiratory function. Indices of lung function may fall as much as 50% in a year and chest infections may require frequent admissions to hospital. The respiratory symptoms are often attributed to CF related lung disease and affected children may therefore be considered unsuitable for liver transplantation. We propose a simple scoring system which can help to select patients who should be referred for assessment of liver transplantation. After careful assessment and preparation children with lung function indices as low as 30% predicted can have a successful outcome after liver transplantation. With good graft function portal hypertension is relieved and absorption, nutrition and respiratory function all improve. The improved quality of life of these children is remarkable.