How should and how could nation states react efficiently to the growing complexity of contemporary migration patterns? What are the criteria to assess the efficiency and effectiveness of migration policies? Politicians want the right answers. Economists want the right answers for the right reason. Although economic considerations alone do not determine migration policies, they can play a critical part in policy-making from a double perspective. First, economic arguments about the costs and benefits of migration provide a framework for determining the possibilities and limitations of a migration policy regime to regulate the impact of labour inflows. Second, the economic approach proved to deliver good tools for analysing the underlying mechanisms of national and supra-national migration policy-making as such. Who are the losers and winners of specific changes in migration policies? To what extent is a migration policy measure beneficial for which groups in the receiving country? Will a relaxation of migration restrictions harm the development in the sending countries? In what follows, some insights from economics will be presented in order to support this double perspective. First, conditions of an efficient migration policy will be discussed. Efficiency in this context means that political goals should be reached with minimal costs. Thus, the first step is to argue why, from an economic point of view, migration should be regulated at all and how. Second, economic analysis will be applied to migration policy-making. Using insights from the ‘theory of clubs’, national and international implications of migration policies are analysed. This will assist the understanding of why a supra-national framework to regulate international migration might be helpful in balancing the benefits and the controversial negative effects of free international migration.