Fever in infants and toddlers can portend a serious bacterial illness requiring a prompt medical response. When dealing with a febrile child between 1 and 36 months of age, physicians should consider toxicity, focal infections, age, and the results of a sepsis workup and then use a strategy based on the Rochester criteria to assess whether the patient is at low risk for a serious bacterial illness. On the basis of that determination, a plan for inpatient or outpatient management can be selected. Variations in treatment can reasonably be based on clinical judgment and physician and parent preferences.