The long run effect of migration solely by unskilled workers is that skilled workers in the home country acquire additional human capital yet their share in the country’s workforce falls. Consequently, the country’s average level of human capital is lowered.

Strong ties with the home country and with the host country can coexist. An altruistic migrant who sends remittances to his family back home assimilates more the more altruistic he is, and also more than a non-remitting migrant.

In the model of Stark et al. (1997, 1998), the possibility of employment in a developed country raises the level of human capital acquired by workers in the developing country. We show that this result holds even when workers have the option to save.

In response to the imposition of steep enough sanctions for employing illegal migrants, the firm reassigns managers from supervision of production to verification of the legality of its workforce. This impedes production efficiency, reduces wages, and hurts the native workers.