This monograph is published by the World Health Organization and is available in English, French, and Spanish. It was made possible through a grant from the Helen Keller International Foundation in New York and from the US Agency for International Development. The author is a distinguished American ophthalmologist who is now the principal investigator of the Indonesian Nutritional Blindness Prevention Project and visiting professor in Bandung, Indonesia. Xerophthalmia is the leading cause of blindness among young children in the developing world and one of the most frequent causes of blindness in general. Dr Sommer estimates that up to 250,000 children in Asia alone lose their sight because of this disease each year and another five to ten million are at risk. This monograph describes assessment, prevention, and evaluation procedures of this condition. It is illustrated with beautiful photographs, most of which are in color and complement the text very well.