The first Human Development Report in 1990 opened with the simply stated premise that has guided all subsequent Reports: “People are the real wealth of a nation.” By backing up this assertion with an abundance of empirical data and a new way of thinking about and measuring development, the Human Development Report has had a profound impact on development policies around the world.

This 20th anniversary edition features introductory reflections by the Nobel Prize–winning economist Amartya Sen, who worked with series founder Mahbub ul Haq on the conception of the first Human Development Report and contributed to and inspired many successive volumes.

The 2010 Report continues the tradition of pushing the frontiers of development thinking. For the first time since 1990, the Report looks back rigorously at the past several decades and identifies often surprising trends and patterns with important lessons for the future. These varied pathways to human development show that there is no single formula for sustainable progress—and that impressive long-term gains can and have been achieved even without consistent economic growth.

Looking beyond 2010, this Report surveys critical aspects of human development, from political freedoms and empowerment to sustainability and human security, and outlines a broader agenda for research and policies to respond to these challenges.

As Amartya Sen writes: “Twenty years after the appearance of the first Human Development Report, there is much to celebrate in what has been achieved. But we also have to be alive to ways of improving the assessment of old adversities and of recognizing—and responding to—new threats that endanger human well-being and freedom.”

The 20th anniversary edition is a response to that human development imperative.