Migration has historically been a source of opportunities for people to improve their lives and those of their families. Today, the large differences in income between places-particularly countries-continue to motivate individuals to escape poverty through migration. The potential advantages of migration for sending countries are numerous. Through remittances, migration provides a means of improving income and smoothing consumption; it enables households to overcome the lack of credit and cushion the risks involved in engaging in more productive activities; and migration can also act as a coping strategy in times of distress. Remittances can be spent on investments, such as housing and schooling, and directly on household consumption. Furthermore, new skills and education may be acquired at the place of destination and transferred back to the place of origin. This volume argues that although migration increases income and often reduces poverty, the migration opportunities of the poor are different-among the poor there are fewer migrants, and they travel to 'cheaper' destinations with lower returns. The main barriers to emigration encountered by the poor are lack of opportunities and high costs. This translates into lower returns and, very likely, less poverty reduction. As a result of this cyclical interconnection, the poverty-reducing potential that migration holds for developing countries is often not maximized.