Patients with indwelling ventricular shunt devices are subject to many complications throughout their lives. This most commonly includes obstruction, infection, and malfunction secondary to loss of placement or connection. Emergency Physicians will see patients of all ages with shunts and who present with headache, fever, nausea, vomiting, seizures, irritability, or a change in mental status. The challenge, frequently a formidable one, will be to determine whether or not the patient's complaint is related to the shunt. This chapter discussed some of the common shunt complications and an approach to their diagnosis. The head CT, the plain film shunt series, and the shunt tap will prove most useful. Of course, a careful history and a skilled physical examination will set the Emergency Physician on a path toward a good outcome for the patient. A Neurosurgeon should be consulted if available. A conservative approach to diagnosis, management, and patient disposition is strongly recommended due to the life-threatening nature of shunt complications.