Esther Duflo at TED

The MIT Economist who won the John Bates Clark Medal:

The award is considered one of the most prestigious honors within economics [..] Many consider the Clark Medal to be a preview of future Nobel prizes, as 12 of the 31 prior Clark Medalists have gone on to receive the Nobel Memorial Prize in Economic Science (including Paul Krugman and Milton Friedman).

Here is a video of her talk on using randomized trials to evaluate which development policies work.