There are at least two reasons to celebrate Frank Knight this year: the centenary of his great work Risk, Uncertainty and Profit (henceforth referred to as RUP) and the more general sense that uncertainty is now a central concern of societies. There is at least one good reason to do so here in Enterprise & Society (ENSO): Knight’s work delivers one of the first economic theories of the firm, and this theory is directly associated with a theory of the functioning of societies.