In 2010, UNICEF predicted that investing in the health and survival of the poorest children would be more cost-effective, even though the costs of reaching them are higher, because the additional costs would be outweighed by greater results. Now, new data and analysis back up UNICEF’s prediction. This study indicates that the number of lives saved per million dollars invested among the poorest is almost twice as high as the number saved by equivalent investments in less poor groups.