Focal cortical dysplasia (FCD) is a definable disorder among the malformation due to abnormal cortical development (MCD) and as such it should be recognized and diagnosed accordingly. The molecular mechanisms mediating epileptogenesis in FCD are not well understood despite the fact that FCD is one of nature's best models for intrinsic epileptogenicity. The clinical manifestations of patients with cortical FCD are variable. Ictal electroencephalogram (EEG) studies have suggested that FCD is a neural network disorder with secondary ictal zones. Intraictal activation is typical of FCD and can be contiguous or at a distance from the primary epileptogenic area. In transmantle cortical dysplasia (TCD), the imaging abnormality extends from the ventricle to the cerebral cortex. The extent and the localization in Bottom of the sulcus FCD (BOSD) distinguish it from TCD or other FCDs. New surgical treatment options that combine network disconnection and augmentation such as electrical stimulation are being developed.