The trafficking in women and girls for the purpose of sexual exploitation worldwide has startled policy makers. Despite efforts to tackle this crime, the magnitude of victims remains. Simultaneously, the dimension of sex trafficking varies, both within origin as well as destination countries. In this dissertation Sofia Jonsson asks why this is the case by examining how, and to what extent the state may shape the incentive structure of this illegal trade. The main findings of the dissertation suggest that the state in its role as law enforc-er, and law maker, might enable crime groups, intentionally and unintentionally, to increase their profit, by constituting the environment that shapes incentives for both supply and demand in the transna...