Nicholas Kristof explains why aid is hard.

In rural Indonesia, you see a cultural problem that aid can't easily address: pregnant women and babies going hungry, even having to eat bark from trees, while their husbands are doing fine. It turns out that the custom is for the men and boys to eat their fill first.

Discouraged, you move on to southern Africa. You see the very sensible efforts of aid groups to get people to grow sorghum rather than corn, because it is hardier and more nutritious. But local people aren't used to eating sorghum. So aid workers introduce sorghum by giving it out as a relief food to the poor—and then sorghum becomes stigmatized as the poor man's food, and no one wants to have anything to do with it.

William Easterly, in his tremendously important and provocative new book, The White Man's Burden, asserts with great force that the aid industry is deeply flawed.