This chapter focuses primarily upon one main issue of immigration: the labor market adjustments made by the foreign born in the destination and their earnings and unemployment experiences over time. It discusses In the process some related concepts, such as the determinants of immigration and the endogenous effects of native worker internal migration. A simple economic migration model defines a person's decision to migrate as a function of the expected difference in wages between the origin and the destination and the expected costs of the migration. Immigrants often arrive at a destination with distinct disadvantages in human capital specific to the destination labor market. The motivation for immigration and the transferability of initial skills are several important differences between groups. The description far of theories of immigration have considered only the effects of assimilation, self-selection, and cohort quality on earnings.