For patients with inadequately treated epilepsy, tremor, dystonia, spasticity, depression, obsessive-compulsive disorder, Parkinson's and Alzheimer's disease, functional neurosurgery offers hope. Functional Neurosurgery: The Essentials is a reader-friendly introduction to this fascinating and rapidly evolving field. The text is edited by internationally prominent functional neurosurgeons Jeffrey A. Brown, Julie G. Pilitsis, and Michael Schulder. It features contributions from authors with expertise spanning the disciplines of neurosurgery, neurology, rehabilitation and physical medicine, neurophysiology, bioengineering, psychiatry and ophthalmology. Opening with a brief history of stereotaxy/functional neurosurgery and brain stereotactic frames, 41 concise and coherent chapters explore cutting-edge approaches to a broad range of functionally treatable conditions. The chapters yield a solid foundation of understanding of the field, with insightful commentary, pearls, and nuances from the editors. The starting question in the neuroprosthetics chapter, "Can a computer infer human intention or perception?" brings to life the exciting, inquisitive, and pioneering spirit of this subspecialty. The robust reference list provides a guide to deeper study that should continue throughout training and practice.