This is a book about how we should address the great, and interconnected, global challenges of the twenty-first century. Our task, Sachs argues, is to achieve truly sustainable development, by which he means finding a global course which enables the world to benefit from the spread of prosperity while ensuring that we don’t destroy the eco-systems which keep us alive and our place in nature which helps sustain our values. How do we move forward together, benefitting from our increasing technological mastery, avoiding the terrible dangers of climate change, mass famines, violent conflicts, population explosions in some parts of the world and collapses in others, and world-wide pandemic diseases?