What explains the popularity of law and economics (L&E) in some academic communities and the scarcity of such scholarship in others? Many explanations have been given for the centrality of economic analysis in American legal thought and its marginality in Europe. This article examines what drives scholars to select L&E as a topic for research. It does so by implementing the methodology of many papers in the field – by assuming that regulation and incentives matter. Legal scholars face very different academic incentives in different parts of the world. In some countries, the academic standards for appointment, promotion and tenure encourage legal scholars to concentrate on L&E. In others, they strongly discourage such research. Thus, we should expect wide variation in the participation rate of legal scholars in the L&E discourse across countries. On the other hand, economists are evaluated with similar yardsticks everywhere, and thus their participation rate is likely to vary much less. The hypothesis of this paper is that academic incentives are a major factor in the level of participation in L&E scholarship. This "incentives hypothesis" is presented and then examined empirically with data gathered from the list of authors in L&E journals and the list of participants in L&E conferences. The data generally support the hypothesis. In legal academia, the incentives to focus research on L&E topics are the strongest in Israel, weaker in North America, and weakest in Europe. In fact, the data reveal that lawyers' authorship of L&E papers weighted by population is about ten times higher in Israel than in North America; while in Europe it is almost five times lower than in North America. By comparison, the weighted participation level of economists – who face relatively similar academic environments across countries – in L&E research is not significantly different across countries.