Based on the current European discussion about immigration policy, this paper gives an overview of central economic consequences of immigration for a host country=s labor market. The most important theoretical arguments are presented and evaluated against the available empirical evidence. The paper concludes that immigration cannot per se be considered as good or bad for the labor market. Its impact on employment, wages and wealth depends crucially on the design of immigration policy. Immigration of selected workers may create gains in efficiency which also result in positive distributive effects, not only for capital but also for native labor.