The Japanese population, the longest-lived in the OECD, is undergoing a profound transformation. Japan’s birth rate has been falling; based on OECD projections by 2050 36.4% of Japan’s population will be over 65, and 15.0% over 80, making Japan’s population older than that of all other OECD countries. In some ways, Japan’s public health challenges are unlike those of other OECD countries. Japan’s obesity rate is the lowest in the OECD (23.8% of the population was overweight or obese in 2015, compared to the OECD average of 53.9%), the rate of smoking is slightly below the OECD average (18.3% of the population were daily smokers in 2015, compared to the OECD average of 18.5), and alcohol consumption is well below the OECD average. In many other respects, though, the health challenges that Japan is facing are very familiar: in particular, a rising burden of chronic disease, and a rising number of frail and elderly persons. In addition, Japan faces some relatively unique public health risks, notably a significant exposure to natural hazards such as earthquakes, floods, typhoons, and tsunamis. In some instances, these risks have intersected – for example the frail elderly have been particularly affected by some natural hazards.