Apart from control of the seizures, two of the most important factors in determining how well a child with epilepsy progresses toward independence are cognition and behavior. The diagnosis of the correct epilepsy syndrome often provides information with regard to probability of good seizure control and intellectual outcome. However, relatively little has been published on the behavioral aspects of the various epilepsy syndromes. In West syndrome there is emerging evidence that early effective treatment might improve outcome in terms of both cognition and behavior. The work on this syndrome in children with tuberous sclerosis has demonstrated an association between temporal lobe tubers and autism. In Dravet syndrome, a variety of psychiatric disorders have been reported, including hyperactivity and autistic features. This is another epilepsy syndrome that tends to be resistant to treatment, implying that the prognosis has to be guarded. The behavioral problems reported with Lennox–Gastaut syndrome also include autistic features, as well as generally sluggish behavior. It is very likely that these characteristics largely reflect the effect of ongoing seizure activity. Autistic features, aggression, and hyperkinesis have been described with Landau–Kleffner syndrome. The behavior may improve dramatically with appropriate medical treatment or after multiple subpial transection. Although the syndrome of benign partial seizures with centrotemporal or rolandic spikes is said to have a very good prognosis, it is becoming increasingly evident that behavioral problems such as concentration difficulties, tempers, hyperactivity, and impulsivity might occur. Juvenile myoclonic epilepsy has been associated with very variable behavioral traits, sometimes with immature personality features and poor social adjustment suggesting frontal lobe dysfunction. Because many of the reports of behavioral disturbance associated with epilepsy syndromes are anecdotal and do not include validated measures of behavior it would be unwise to draw firm conclusions from them at this stage. Carefully conducted prospective studies, paying particular attention to any behavioral improvements that occur with successful treatment of the epilepsy, are required.