Abhijit Banerjee starts the debate on international aid to poor countries and how to make it work, that leads to quite a few responses. The following excerpt is the central point in Banerjee's article:
Randomized trials ... —- that is, trials in which the intervention is assigned randomly -— are the simplest and best way of assessing the impact of a program. They mimic the procedures used in trials of new drugs, which is one situation in which, for obvious reasons, a lot of care has gone into making sure that only the interventions that really work get approved, though of course not with complete success. In many ways social programs are very much like drugs: they have the potential to transform the life prospects of people. It seems appropriate that they should be held to the same high standards.