Vitamin A deficiency remains a major cause of pediatric ocular morbidity. Over five million children develop xerophthalmia annually, a quarter million or more becoming blind. It is also a major pathway for measles-associated blindness, particularly in Africa. Treatment is practical and inexpensive, based upon the oral administration of 200,000 IU vitamin A on two successive days, at a cost of 10 cents U.S. Given the potential rapidity of corneal necrosis (keratomalacia) and the relative inaccessibility of health services to those at greatest risk, prevention is probably more important than treatment. Oral administration of high dose supplements (2000,000 IU every 3 to 6 months), vitamin A fortification of commonly consumed items, or best of all, increased dietary intake of natural sources of vitamin A will reduce the number of needlessly blind young children. Given recent evidence that vitamin A deficiency greatly increases overall mortality, even among children without evidence of xerophthalmia, the same prophylactic regimen may improve child survival by 35% or more.