Two experts in foreign aid are debating how to best help poor people in Africa and developing regions of the world — and the public spat is turning more personal.

Jeffrey D. Sachs, director of Columbia University’s Earth Institute, and William Easterly, a professor of economics at New York University, have been butting heads for several years and recently exchanged barbs on The Huffington Post, an online newspaper.

Speaking about Mr. Easterly and another aid critic, Mr. Sachs writes: “Before peddling their simplistic concoction of free markets and self-help, they and we should think about the realities of life, in which all of us need help at some time or other and in countless ways, and even more importantly we should think about the life-and-death consequences for impoverished people who are denied that help.”

Mr. Easterly returns fire, calling Mr. Sachs “the world’s leading apologist and fund raiser for the aid establishment” and saying that the Columbia professor is trying to stifle debate about foreign assistance.

What do you think? With their disagreement likely to continue, are donors or international aid groups paying attention to it?