This document discusses the pupillary pathway and various pupillary disorders. It begins by describing the development of the pupil from the pupillary membrane. It then discusses the muscles that control pupil size and various reflexes like the light and accommodation reflex. It describes different types of pupil abnormalities including iris colobomas, aniridia, traumatic causes and neurological causes. Specific disorders like Horner's syndrome and Adie's tonic pupil are explained in detail. Pharmacological tests to localize lesions in different parts of the pupillary pathway are provided. The document concludes by mentioning some references.