When economic sociology appeared on the academic scene in the mid-1980s its interactions with New Institutional Economics were soon plentiful as well as productive. Especially the ideas of Oliver Williamson and Douglass North were often discussed and found useful. That this was a fruitful interaction is exemplified not least by the fact that Williamson’s notion of “hybrid” was developed in response to comments on his distinction between markets and hierarchies by some sociologists. The concept of “transaction cost” soon became part of the sociological language, and sociologists suddenly seemed more receptive to ideas of economists than they had been for a very long time.