 So, yn 1985, dr Hannah Falf from the Gambia did a survey of eye diseases in the Gambia and she showed that there were 7,000 blind people in the Gambia, mainly from cataract and trachoma. She was working as an ophthalmologist in the country, she could have just carried on doing her work day by day and so on. But she decided no that change was needed to address this problem of avoidable blindness in the Gambia. So she set about a plan. Now to do that plan she had to sit down, she had to kind of think where are we, what's the situation today and how do we want it to be in the future and what do we need to do. And gradually she developed that plan and that plan was all about training eye care teams to address the problem of cataract and equipping them and also addressing the issues of trachoma through primary healthcare and training primary eye care workers. And gradually year by year she implemented that plan bit by bit, step by step and she didn't do it for one year or two years she kept doing it. But at the end of 10 years a survey was done again in the Gambia and that showed that blindness had been reduced by 40% over the 10 years, more than 2,000 people had been saved from blindness. And the cost of doing it was actually less than 10 cents per person per year. So it was a very kind of effective program, it wasn't very expensive but it made a big difference in the lives of people. So there was a plan taken quite a long time to develop but a plan to change from one eye doctor in one hospital to several cataract surgeons in the country and all the health workers being trained in prevention of blindness and good eye care and she managed to achieve it. So that's a good example of what was done and that then actually became a model for the Vision 2020 program to replicate that district by district.