Cerebral edema is the leading cause of death in children presenting in diabetic ketoacidosis and occurs in 0.2 to 1% of cases. The osmolar gradient caused by the high blood glucose results in water shift from the intracelluar fluid (ICF) to the extracellular fluid (ECF) space and contraction of cell volume. Correction with insulin and intravenous fluids can result in a rapid reduction in effective osmolarity, reversal of the fluid shift and the development of cerebral edema. The goals for treatment should be a combination of intravenous fluid and insulin that results in a gradual reduction of the effective osmolarity over a 36- to 48-hour period, thereby avoiding rapid expansion of the ICF compartment and brain swelling.