• Primary open-angle glaucoma, the most common form, is asymptomatic until late in the course of disease, and irreversible vision loss can occur silently. • Screening tests are imperfect and there is a need to stratify individuals according to risk. • There are different risk factors, symptoms, signs and treatment of acute angle closure versus chronic open-angle glaucomas. • Current therapies are aimed at reducing the intraocular pressure (IOP), and medical management is the mainstay. • Glaucoma therapies have the potential for adverse effects both locally and systemically and for systemic interactions with other drugs. • There is a spectrum of severity and some patients are at risk of severe visual loss. These cases need to be identified and more aggressively managed, often requiring surgery to control the IOP.