Epilepsy, also called seizure disorder, is the most common childhood brain disorder in the United States. The aetiology of epilepsy in children is multifactorial with congenital, metabolic, infective, and problems associated with prematurity being common causes. Nearly 3 million Americans have epilepsy. About 450,000 of them are under 17 years old. About 1 in 200 children (0.5%) have epilepsy, a neurological condition where children have a predisposition to recurrent, unprovoked seizures. There are many different types of epilepsy, especially in infancy, childhood and adolescence. Epilepsy can be thought of in terms of either: the site of seizure origin in the brain (generalised or focal seizures), or the underlying cause. Genetic epilepsies (formerly called idiopathic or primary epilepsies) occur in an otherwise normal person and are due to a genetic predisposition to seizures. Some epilepsies are due to an underlying abnormality of the brain structure or chemistry (formerly called symptomatic or secondary epilepsies). Other epilepsies have no known cause. Epilepsy is commonly diagnosed in children and can be confused with other conditions. An accurate diagnosis is essential. A seizure is an excessive surge of electrical activity in the brain that can cause a variety of symptoms, depending on which parts of the brain are involved. Seizures can be provoked or unprovoked. Provoked seizures, caused by fever in a young child or severe hypoglycemia, are not considered to be forms of epilepsy. Unprovoked seizures have no clear cause but can be related to genetics or brain injury. When a child has two or more unprovoked seizures, epilepsy is often the diagnosis. Despite advances in antiepileptic medication therapy, a significant number of pediatric patients with epilepsy have seizures that are not well controlled. Antiepileptic medications interact with anesthetic agents, and common anesthetics can precipitate or suppress seizure activity. There are important pharmacokinetic and pharmacodynamic interactions between AEDs and drugs commonly used in anaesthesia. These affect both drug efficacy and the risk of seizure activity intraoperatively.