 Hello and welcome to week three. Cataract occurs across all populations. We have effective surgical treatment and yet cataract blindness remains one of the main causes of blindness in many low and middle income countries. How can service provision increase the number of surgeries and also ensure high quality of these services? If they are going to do all these activities, how can they make sure it is sustainable? In this week, we will be hearing from experts from around the world and from Nigeria we will hear about the challenges that they face in the delivery of cataract services. And from the other end of the spectrum, from the Aravind eye health system on high volume, high quality service provision. We will also look at the role of innovation such as the peak mobile phone technology and how can that be used to improve service provision at a local level.