 Global estimates suggest that there are approximately 36 million people who are visually impaired, 216 million people with moderate to severe visual impairments, and 188 million people with mild visual impairments. Additionally, 1095 million people over the age of 35 have functional presbyopia. This article was authored by Professor Rupert I. Born, M.D., Seth A. Flaxman, B.A., Tasani Braithwaite, Miles Perrower, and others.