This document discusses the scalp block technique. It begins by describing scalp block as local anesthesia of the scalp nerves. It then discusses the history and development of scalp block, including the original description in 1986 and studies in the 1980s that demonstrated its effectiveness in reducing hemodynamic changes during craniotomy. The document outlines the specific nerves blocked in scalp block and techniques for each, and notes bupivacaine is often used. Advantages include decreased blood pressure and intracranial pressure changes during surgery. Potential complications are also reviewed. Finally, it briefly discusses recent updates to the Glasgow Coma Scale including the addition of a pupil reactivity score in 2018.