I Cannot Cheat on You after We Talk

This is a draft of a chapter in a planned book on the Prisoner’s Dilemma, edited by Martin Peterson, to be published by Cambridge University Press. - Experimental evidence on pre-play communication supports a “focusing function of communication” hypothesis. Relevant communication facilitates cooperative, pro-social behavior because it causes a shift in individuals’ focus towards strategies dictated by some salient social norm. After reviewing the formal foundations for a general theory of conformity to social norms, we provide an original application illustrating how a framework that allows for different conjectures about norms is able to capture the focusing function of communication and to explain experimental results.