Status epilepticus occurs when seizures do not stop spontaneously; it is the most severe form of epilepsy. We will determine the incidence and causes of status epilepticus in the greater Auckland region. Over a one-year period, we will identify all patients over the age of 4 weeks who present to Auckland, Middlemore, North Shore and Waitakere hospitals with seizures that continue for over 10 minutes duration. Information will be collected regarding the type, cause, duration, treatment, and outcome for each episode of status epilepticus. Blood samples will be tested for the presence of anti-neuronal antibodies. Patients will be followed for two years, so that the long-term global outcome, and associated health costs can be determined. We need to determine why people in New Zealand develop status epilepticus, and which treatments work best, so that we can reduce its frequency, and the morbidity and mortality associated with it.