Perioperative management of newborn and infants is quite different from the perioperative management strategy in adults. Infants have quite a different response to surgical disease and intervention that must be recognized by the clinician. Thermoregulation, metabolic changes, resuscitation principles, fluid and electrolyte management, and nutritional needs are quite different in the pediatric population. Not only are physiologic parameters different, but also many of the pediatric surgical anomalies and surgical diseases are unique. This chapter will discuss critical details of perioperative management of neonates and infants and highlight specifics that are unique to various common surgical anomalies.