At least 721 million fewer people live in extreme poverty in the world today than 30 years ago. Poverty reduction surpassed expectations-the Millennium Developing Goal 1 of halving extreme poverty between 1990 and 2015 was reached ve years ahead of time. But to lift the remaining poor out of deprivation, and to end extreme poverty by 2030, the world will have to work harder and smarter as extreme poverty becomes a more difficult problem to solve requiring more targeted and highly effective solutions. To start, we need to know who the extremely poor are, where they live, and where poverty is deepest and harder to end.