Over the past 20 years a silent revolution in functional neurosurgery has been unfolding. This revolution, still in the making, is the development of cortical electrical neuromodulation. No book covering the field of therapeutic cortical stimulation exists and only scarce attention has been given to this new field of neuromodulation in all textbooks and related books. As a result, the majority of neurologists and neurosurgeons are unaware of this technology. The aim of this book is thus twofold: cross-fertilisation among neurologists, other health professionals and functional neurosurgeons, and defining indications and limits of cortical stimulation, invasive and non-invasive. This textbook brings together leading authorities from all over the world and provides for the first time a complete account of the field. As a "teaching" tool, all, beginners and non, will find a conclusive word in a rapidly evolving field.