An awake craniotomy for tumour and epilepsy surgery allows for the mapping of eloquent brain function to minimize its injury and/or for the localization of an epileptic focus. The insertion of deep brain stimulators for the treatment of functional neurosurgical disorders is also frequently performed with an awake patient. The role of the anaesthetist is important in order to have a comfortable and cooperative patient, for the use of appropriate sedation to allow for mapping, and careful vigilance to rapidly diagnose and treat any complication. This chapter discusses the overall rationale for, and the anaesthetic management of, patients undergoing awake craniotomy for tumours, epilepsy surgery, or deep brain stimulator placement.