Economics of Social Capital*

The literature on the idea of ‘social capital’ is now enormous. Offering an alternative to impersonal markets and coercive states, the communitarian institutions built around social capital have looked attractive to scholars in the humanities and social sciences. The literature in consequence has a warm glow to it. In this article, I first study the various contexts in which the promises people make to one another are credible and then suggest that the accumulation of social capital is a possible route to creating such a context. I offer a tight definition of social capital – namely, interpersonal networks – so as not to prejudge its ability to enhance human well‐being. The links between the microfoundations of social capital and the macroeconomic performance of economies are then studied. I also show that economic theory not only identifies circumstances in which communitarian institutions can function well, but that it also uncovers a dark side, namely, their capicity to permit one group to exploit another within long‐term relationships.