Prevention of bilirubin encephalopathy is based on the detection of infants at risk of developing a significant hyperbilirubinemia. This task can be accomplished by performing a simple umbilical cord blood test, such as blood group, Rh, Coombs’ test and glucose-6-phosphate dehydrogenase, in order to detect hemolytic diseases. In preterm infants, the prevention of hyperbilirubinemia with phototherapy is a relatively simple task, since these infants are cared for in hospital. Early hospital discharge of full-term neonates represents a major concern. The management of neonatal jaundice requires that therapy begins when total serum bilirubin levels are significantly below the levels at which kernicterus is considered an immediate threat. Unfortunately, determination of serum bilirubin is a painful procedure, and is not very accurate since there is a high variability in laboratory measurements. The accuracy and precision of a new transcutaneous bilirubin measurement, comparable to the standard of care laboratory test, makes the daily evaluation of transcutaneous bilirubin measurement a useful tool in distinguishing physiological from nonphysiological hyperbilirubinemia, and determining the bilirubin increment in the first days of life. Full-term neonates who lose a significant amount of weight are especially at risk of significant hyperbilirubinemia and must be treated with ad libitum feeding and intensive phototherapy.