 Why does health matter? In Japan, we have a name that says KENKO DAICHI. It means health first, and everything else comes after. You need to be healthy. You need to be alive in order to go to school, to go to work, to have a family, and to be happy. And this basically applies to the link between health and wealth at the more population and national level. What's the link between health to wealth? The other way, wealth to health is quite clear. The wealthier you are, more access to health care and resources to make you healthy. But also, it's bidirectional. If the workforce is healthy, it's more productive. And if children are healthy, they benefit more from education. And the parents see education as an investment. If people have longer years to live, they start thinking about the future and invest and to save for the future. Healthy population can also have effect on the demographic dividend. This was what we saw in the late 20th century in Asian countries, where there was a cohort of young, healthy, educated, productive workers that gave boost to the countries. We have seen a remarkable progress in the last 25 years. Under five child mortality has declined from 13 million in 1990 to 6 million in 2013. That's a remarkable progress. And at the same time, development assistance for health has really increased. And in the recent years, the annual disbursement is above $35 billion a year. So that leaves me a question. Why do we see a decline in child mortality and how effective has all development assistance for health been? This is one of the core questions that I have. There's a few elements to my research. One is how do we measure what's happening? So this applies to all economics, a matter of how to measure things. One theme issue that we're doing, which will come out in June 2017 in bulletin of World Health Organization, is a theme issue on measuring quality of care. We need to move beyond counting number of bed nets, number of hospital beds, and number of people vaccinated. We need to know what's happening with the quality of healthcare because the outcome is not necessarily improving in spite of the increase in quantity. Measuring quality is very different. It's very challenging compared to measuring something countable. Another thing that I'm looking at is on intergenerational effect of health and how gender inequality affects this. We looked into what key health interventions, such as vaccination, breastfeeding, bed nets to protect against malaria, we control for mothers' education and general economic development. And we found that key health interventions, such as vaccination and breastfeeding, were highly associated with child survival. The key takeaway is we have seen progress in the last 25 years. There's more investment in child health and we have seen reduction in child mortality. But perhaps now it's time to look into what were the most effective interventions and have we really put our resources in these interventions.