The highlights of this chapter are an account of the various structures of the brain, CNS localization, cranial nerve diagram, innervations of bladder, UMN and LMN paralysis, CNS infections namely pyogenic and TB meningitis, brain abscess, encephalitis, Differential diagnosis of Microcephaly- primary and secondary, macrocephaly, megalencephaly, hydrocephaly, Definition and differential diagnosis of Acute flaccid paralysis, various aspects of Poliomyelitis eradication programme and vaccine associated polio (VAP).