Status epilepticus (SE), defined as clinical or electrical seizures continuing for at least 30 minutes, occurs in a minority of patients with epilepsy and is more common in symptomatic than in idiopathic forms. In adults, brain tumor, trauma, and stroke account for a substantial proportion of cases, whereas in children, various infectious processes, toxic or metabolic disorders, and chronic encephalopathies may be found. SE is often precipitated by sudden withdrawal of anticonvulsant drugs or intercurrent infection. Prolonged seizures lead to a series of metabolic derangements which may subsequently cause neuronal damage. Therapy aimed at preventing this sequence of events includes general measures, such as ensuring sufficient oxygenation, maintaining adequate blood pressure, and preventing hyperthermia or hypoglycemia. Specific anticonvulsant drug therapy is reviewed, including recommended doses, mode and rate of administration, and potential hazards.