A single social program is transforming how countries all over the world help their poor.
The city of Rio de Janeiro is infamous for the fact that one can look out from a precarious shack on a hill in a miserable favela and see practically into the window of a luxury high-rise condominium. Parts of Brazil look like southern California. Parts of it look like Haiti. Many countries display great wealth side by side with great poverty. But until recently, Brazil was the most unequal country in the world.
