David Leonhardt asked around:
So when I recently set out to conduct my second annual survey of economists, I decided to try to uncover the next best thing. In its first incarnation, the survey simply asked for the names of the next generation of stars specializing in the economics of everyday life. This year, though, I went the other way — toward the big picture — and asked which economists were managing to do influential work on the crucial questions facing modern society.
Who, in other words, was using economics to make the world a better place?
I received dozens of diverse responses, but there was still a runaway winner. The small group of economists who work at the Jameel Poverty Action Lab at M.I.T., led by Esther Duflo and Abhijit Banerjee, were mentioned far more often than anyone else.