In an overview of studies on India in the United States, Devesh Kapur of the University of Pennsylvania has some less than complimentary things to say about RCTs. They mirror some of my comments about systematic reviews here, the next layer of RCTs, though I do not say anything about the benefits to reseachers like Devesh does. By contrast, there has been a considerable increase in India-related work in the social sciences. The field has become much more empirical and India offers several advantages for a researcher: large sample sizes, heterogeneity in multiple dimensions, relatively low cost of gathering data, and weak official oversight (which, in any case, is unlikely to be enforced). It would be hard to do many of these trials in the US or China.