This chapter provides an overview of the anatomy and function of the central nervous system (CNS), emphasizing its significance in anesthesia. The CNS, comprising the brain and spinal cord, is integral to controlling consciousness, sensory processing, motor function, and homeostasis—all critical aspects influenced by anesthetic agents. Key structures such as the cerebral cortex, basal ganglia, brainstem, cerebellum, and spinal cord are examined for their roles in mediating neural pathways and responses during anesthesia. Protective mechanisms, including the blood-brain barrier, cerebrospinal fluid (CSF), and meninges, are highlighted for their importance in anesthetic pharmacokinetics and neuroprotection. By bridging neuroanatomy with anesthetic considerations, this chapter sets the foundation for understanding how anesthesia alters CNS function to achieve sedation, analgesia, and loss of consciousness.