Glaucoma is a chronic progressive optic neuropathy caused by a group of conditions leading to damage to optic nerve with loss of visual function. Raised intraocular pressure is the most important risk factor. Outflow of aqueous occurs through the angle of anterior chamber (conventional route) or through the uveoscleral route to the episcleral venous system. Glaucoma may be congenital or acquired, primary or secondary, open angle or closed angle. Congenital glaucoma or buphthalmos occurs between birth and 3-4 years of age. Lacrimation, photophobia, enlargement of eyeball, corneal oedema, Haabs striae are the characteristic clinical features. Goniotomy, trabeculotomy and trabeculectomy are the surgical options. Primary open angle glaucoma is chronic and slowly progressive and is diagnosed by the classical triad signs of raised intraocular pressure, cupping of the optic disc along with characteristic visual field defects. Medical treatment is the initial treatment of choice. Trabeculectomy is a filtering surgery usually done when medical treatment fails. Argon or diode laser trabeculoplasty are other treatment options. In primary angle closure glaucoma the intraocular pressure is raised due to obstruction to the outflow of aqueous. There is relative pupillary block with physiological iris bombe formation leading to irido-trabecular contact. The clinical course progresses from latent, subacute or intermittent stages to the stages of acute, chronic and absolute glaucoma. Medical treatment is used to lower the tension preoperatively. Surgical treatment is the mainstay and consists of laser iridotomy and trabeculectomy according to the stage of glaucoma. Glaucoma may also occur secondary to causes like inflammation, corneal perforation or may be lens induced.