The field of human stereotactic surgery began when Spiegel and Wycis introduced their stereoencephalotome in 1947, reached its epitome in the early 1960s, and declined sharply after the introduction of l-dopa in 1968. When the development of implantable stimulators provided an abrupt expansion of techniques in nonstereotactic functional neurosurgery, the field became “stereotactic and functional neurosurgery.” The marriage of stereotactic surgery with computed tomography has reawakened the use of stereotactic surgery and brought it closer to general neurosurgery than ever before. Stereotactic and functional neurosurgery as a subspecialty has expanded rapidly and will continue to expand at an unprecedented rate, with significant changes reflecting the continuing advances in technology begun 15 years ago. It is becoming an increasingly important part of the field of neurosurgery and has extended its influence in many new clinical areas previously outside the realm of stereotaxis.