Thirty years ago, UNDP created a new way to conceive and measure progress. Instead of using growth in GDP as the sole measure of development, we ranked the world's countries by their human development: by whether people in each country have the freedom and opportunity to live the lives they value. The 2020 Human Development Report (HDR) doubles down on the belief that people's agency and empowerment can bring about the action we need if we are to live in balance with the planet in a fairer world. It shows that we are at an unprecedented moment in history, in which human activity has become a dominant force shaping the planet's key processes – the Anthropocene. These impacts interact with existing inequalities, creating unparalleled threats of human development reversal and exposing weaknesses in social, economic, and political systems. Though humanity has achieved incredible progress, we have taken the Earth for granted, destabilizing the very systems upon which we rely for survival. COVID-19, which almost certainly sprang to humans from animals, offers a glimpse of our future, in which the strain on our planet mirrors the strain facing societies. How should we react to this new age? Do we choose to strike out on bold new paths striving to continue human development while easing planetary pressures? Or do we choose to try—and ultimately fail—to go back to business as usual and be swept into a dangerous unknown? This Human Development Report is firmly behind the first choice, and its arguments go beyond summarizing well-known lists of what can be done to achieve it.