The social process of international migration.

The social process of network growth helps to explain the rapid increase in the migration of Mexicans to the United States during the 1970s. Migrant networks are webs of social ties that link potential migrants in sending communities to people in receiving societies, and their existence lowers the costs of international movement. With each person that becomes a migrant, the cost of migration is reduced for a set of friends and relatives, inducing them to migrate and further expanding the network. As a result of this dynamic interaction, network connections to the United States have become widespread throughout Mexico, and the probability of international migration from that country is high.