Summary 4Summary: In recent years our approach to perioperative fluid management in children has undergone a change. For many years hypotonic electrolyte solutions with 5 % glucose added were used for perioperative paediatric fluid therapy but were not infrequently associated with severe hyponatraemia and hyperglycaemia. Currently, isotonic electrolyte solutions are now recommended for both children and adults to avoid the risk of hyponatraemia. In particular in neonates and infants hypoglycaemia and catabolic states can be avoided through the use of fluids with lower glucose concentrations (1 - 2 %), which are now available on the German market. During major surgical procedures with significant blood loss, colloids are more effective for the stabilization of colloid osmotic pressure and plasma volume. In children too, the traditional natural colloids i.e. albumin or plasma protein solutions can now be replaced by the less expensive and equally as effective second and third generation synthetic colloids i.e. hydroxyethyl starch (MG 130.000 or 200.000) or gelatine. Postoperatively early enteral feeding is more physiological and safer than parenteral fluid therapy, and should be given preference whenever possible.