That is, by comparing cohorts of Mexicans who migrated to the US with the same cohorts residing in Mexico it is shown that the highest and lowest educated tend to migrate more than the middle educated. A model is presented that is capable of reproducing this relationship. The model assumes that individuals are endowed with heterogeneous levels of human capital. These levels are determined partly by an intergenerational transmission from their parents and partly by an investment on education also made by their parents. Migration decisions are driven mainly by two forces. On the one hand, there is a progressive loss of human capital faced by immigrants, due to its imperfect transferability. On the other hand, the altruism towards future generations together with the transmission of human capital drives the positive relationship. Finally, the model is calibrated to match relevant moments from the Mexican and US, Censuses and used for policy evaluation. First, the long run effect of the Mexican government run Oportunidades program on the average human capital accumulation among Mexican migrants and non-migrants is evaluated. Second, a US government run restrictive policy, intended to make immigration more difficult, is also evaluated. Overall, the evaluation suggests that the Oportunidades program has effects that are more desirable on the migrants selection and the education distribution of Mexicans than restrictive policies