The relationship between epilepsy and psychiatry is reviewed. It is concluded that patients with epilepsy display more psychopathology than control populations and that patients with temporal lobe epilepsy are especially susceptible to more severe psychiatric illness. Psychosis, particularly with a schizophrenia-like presentation seems associated with dominant hemisphere pathology especially with altered function. The relationship between personality disorder and epilepsy is less clear. Affective disorder is a common clinical problem, although earlier reports of a link with the non-dominant hemisphere have not been replicated in some recent studies. The problem of cognitive decline is examined and it is concluded that many patients with epilepsy show either selective or more generalized impairments of abilities. This may be related to the effects of anticonvulsant drugs, and the possibility that carbamazepine may possess psychotropic properties is noted.