This Article discusses the Palermo Protocol to Prevent, Suppress and Punish Trafficking in Persons. In the first part it offers a critical discussion of what is entailed by speaking of a “shortfall” of enforcement in dealing with the social problem of human trafficking. It then goes on to show that there are two competing narratives of this problem and of the way it is being responded to, and explains why we need to learn more about the interests and values that condition the “law in action.” In the last section the Article discusses the potential relevance of the idea of the “legal culture” for explaining the patterns of “law in action” in different countries and different agencies. The Article's overall aim is to show the existence of a link between the manner in which the problem of trafficking is socially defined in practice, and the role of legal culture in shaping this link.