As a species we have doubled our life expectancy in just one hundred years. This book is Steven Johnson's attempt to understand where that progress came from. How many of those extra twenty thousand days came from vaccines, or the decrease in famines, or seatbelts? What are the forces that now keep us alive longer? Behind each breakthrough lies an inspiring story of cooperative innovation, of brilliant thinkers bolstered by strong systems of public support and collaborative networks. But it is not enough simply to remind ourselves that progress is possible. How do we avoid decreases in life expectancy as our public health systems face unprecedented challenges? What current technologies or interventions that could reduce the impact of future crises are we somehow ignoring? A study in how meaningful change happens in society, Unexpected Life is an ode to the enduring power of common goals and public resources.