Leprosy remains one of the world's major blinding diseases and yet few ophthalmologists are aware of the spectrum of ocular complications. Cross-sectional studies of the eye changes in leprosy patients, made under standardised conditions, have been carried out in 24 different leprosy centres throughout the world and the preliminary results are presented. They show that up to 20% of leprosy patients develop sight-threatening lesions and between 5% and 7% are blind (depending on the definition of blindness). Visual impairment in leprosy needs special consideration by leprologists and ophthalmologists, not only because much of it is preventable, but also because it is a severe burden to be added to the problems of mobility and social stigma that characterise this ancient disease.