Politics matter for human development. Reducing poverty depends as much on whether poor people have political power as on their opportunities for economic progress. Democracy has proven to be the system of governance most capable of mediating and preventing conflict and of securing and sustaining well-being. By expanding people's choices about how and by whom they are governed, democracy brings principles of participation and accountability to the process of human development. This Report is about politics and human development. It is about how political power and institutions—formal and informal, national and international—shape human progress. And it is about what it will take for countries to establish democratic governance systems that advance the human development of all people—in a world where so many are left behind.