From its earliest formulations, economics and sociology of conventions (EC/SC) has developed a systematic interest in law. The specificity of the approach of EC/SC lies in a reexamination of the relationship between code and convention, through the context in which the law is created and the context in which it is realized. A situated and procedural rationality can account for the transformation of legal norms. The law constitutes a universe of rules that cannot be confused with moral norms or conventions of justice (Boltanski and Thévenot’s “economies of worth”). It is a founding institution of modern societies, like money or language. This analysis of law opens the way to two complementary approaches. On the one hand, the places and mediators of law can be analyzed from a convention-based perspective, which replaces the legal consciousness approach with a theory of legal communication. On the other hand, it allows for a pluralist critique of law, based on Blaise Pascal’s definition of tyranny, and takes on an evaluative scope when coupled with an evaluation point of view such as Amartya Sen’s capability approach.