One of the unique roles of the neurohospitalist involves expertise in perioperative neurological issues. This chapter discusses perioperative period in chronological phases. During preoperative phase, neurohospitalists may be called on to provide estimates of neurological risk in order to assist with surgical decision-making. A broad range of chronic neurological conditions may require specific advice and manipulation of therapies in the perioperative period. The chapter discusses specific neurological disorders such as multiple sclerosis. The neurohospitalist is sometimes required to join surgical colleagues in the operating room (OR) to provide real-time interpretation of electrophysiological data such as EEG or somatosensory evoked potentials (SEPs). The first important step in the assessment of patients requiring neurohospitalist consultation is the surgical team recognizing that there is some form of problem, possibly neurological, that requires assessment. Consultations most often arise to assess neurological symptoms rather than obvious diagnosis.