This introduction presents an overview of the concepts discussed in this book The Neuropsychiatry of Epilepsy. In the intervening years, there has been a clear appreciation in biological psychiatry of the neurobiological bases of psychopathologies as major depressive disorder, obsessive-compulsive disorder and other anxiety-related conditions, and there has been further development of psychotropic and anticonvulsant drugs (AEDs). The second edition starts with epidemiology, which has become a prominent discipline in research attempting to disentangle the extent and variety of psychiatric comorbidities in epilepsy. The clinical presentations and the wide spectrum of peri-ictal disorders are then discussed. Depression in epilepsy may not be quite like depression in the absence of epilepsy, the neuroanatomy giving a special stamp on the phenomenology. The book concludes with a discussion on the brain mechanisms of consciousness as may be revealed through investigations of patients with seizure disorders.