Children are at much greater risk than adults for protein-energy malnutrition. This is partly due to their decreased fat and protein stores. These limited endogenous resources, coupled with their increased metabolic demands for growth and development, make them particularly vulnerable to nutritional inadequacy. This is particularly true for the premature or sick term newborn. The tremendous advances in neonatal care over the past two decades have allowed the survival of increasingly smaller and sicker babies. Along with this has been a change in our expectations, nicely characterized by Ekhard Ziegler - "We are no longer content to provide some nutrition within a few days and to gradually increase nutrient intake over several weeks". Part of this plan for earlier provision of optimal nutrition is the use of total parenteral nutrition (TPN). It is particularly valuable for those patients who are unable to take calories by the enteral route.