There are at least 550 million persons with disabilities today who represent around one in ten of the world's population. Around 450 million of them live in developing countries. According to the World Health Organization, 60% of the causes of disability could have been -- or still could be -- alleviated through low-cost preventative measures. In 1992, the director of UNICEF declared that for a few dollars per capita, the parents of the world could be helped to prevent their children from becoming malnourished, blinded, crippled, mentally retarded or dead.