Like many similar countries, the United Kingdom is seeing a rise in modern epidemics such as depression, heart disease, obesity and cancer. We have an excellent NHS that treats these conditions, but what if we could stop them in their tracks? What if they didn't need treating, because they were being prevented? Putting public health at the heart of public policy, this book proposes a radical shift in our priorities as a society and polity: aNational Health Society could make us all healthy. Yuille and Ollier bring together the science of big data and precision public health, with the political change that would be needed to make this a reality. The book forces us to take a step back and see that when it comes to our health, we are not taking it seriously enough.