Nutritional support is an integral part of the management of cystic fibrosis patients. It is arguably best provided by a qualified dietitian and nutritional care sister working in conjunction with the rest of the cystic fibrosis team. The patient's nutritional needs should be assessed, regularly reviewed, and nutritional treatment tailored to meet the changing clinical and psychosocial needs of the patient. Nutritional intervention is not without complications, and in particular attention to normal feeding behaviour and vigilance when instituting supplementary nutrition may prevent many feeding difficulties.