It is one of the most pressing and controversial questions of our time -- vehemently debated, steeped in ideology, profoundly divisive. Who should be allowed to immigrate and who not? What are the arguments for and against limiting the numbers? We are supposedly a nation of immigrants, and yet our policies reflect deep anxieties and the quirks of short-term self-interest, with effective legislation snagging on thousand-mile-long security fences and the question of how long and arduous the path to citizenship should be. In Exodus, Paul Collier, the world-renowned economist and bestselling author of The Bottom Billion, clearly and concisely lays out the effects of encouraging or restricting migration. Drawing on original research and case studies, he explores this volatile issue from three perspectives: that of the migrants themselves, that of the people they leave behind, and that of the host societies where they relocate. Immigration is a simple economic equation, but its effects are complex. Exodus confirms how crucial it will be that public policy face and address all of its ramifications. Sharply written and brilliantly clarifying, Exodus offers a provocative analysis of an issue that affects us all.

As globalization and the flow of labor across the world accelerated during the latter part of the 20th century, the presence of foreign-born workers in a country's labor market became one of the most prominent and controversial features of modern economies. Countries that facilitated the arrival of foreign-born individuals often benefited from the increase in labor supply. An important channel for the benefits is through lower prices for consumer goods and services in the host country. This is not surprising because immigration is just another form of international trade, which often leads to cost savings and more diversity in the market. The immigrants themselves have also gained from international migration as it provides an opportunity to improve one's standard of living, pass remittances to family in the country of origin, and find new opportunities for general human flourishing in newly adopted surroundings.Despite the myriad benefits that can result from the free movement of labor around the world, there is still deep concern and political debate about immigration's aftermath. The main economic concern, apart from social concerns such as social cohesion, centers on whether international migrants adversely impact labor market opportunities of natives.The labor market prospects for foreign-born individuals, both in an absolute sense and in comparison to natives, are also very different across continents, as well as between countries that are in close proximity to one another. This variation could be driven by differences in the flexibility and structure of the host country's labor market or differences in the characteristics of the immigrants themselves. Examining the relative importance of these and other possible factors is another main theme in the study of immigration and the labor market. It is also addressed in the research presented in this Handbook.

International migration, the movement of people across international boundaries to improve economic opportunity, has enormous implications for growth and welfare in both origin and destination countries. An important benefit to developing countries is the receipt of remittances or transfers from income earned by overseas emigrants. Official data show that development countries' remittance receipts totaled 160 billion in 2004, more than twice the size of official aid. This year's edition of Global Economic Prospects focuses on remittances and migration. The bulk of the book covers remittances.

The authors investigate the impact of international migration on child health outcomes in rural Mexico using a nationally representative demographic survey. They use historic migration networks as instruments for current household migration to the United States in order to correct for the possible endogeneity of migrant status. They find that children in migrant households have lower rates of infant mortality and higher birth-weights. The authors study the channels through which migration may affect health outcomes and find evidence that migration raises health knowledge in addition to the direct effect on wealth. However they also find that preventative health care, such as breastfeeding and vaccinations, is less likely for children in migrant households. These results provide a broader and more nuanced view of the health consequences of migration than is offered by the existing literature.

Once viewed as a “brain drain,” migrants are increasingly viewed as a resource for promoting economic development back in their home countries. In Investing in the Homeland, Benjamin Graham finds that diasporans—migrants and their descendants—play a critical role in linking foreign firms to social networks in developing countries, allowing firms to flourish even in challenging political environments most foreign investors shun. Graham’s analysis draws on new data from face-to-face interviews with the managers of over 450 foreign firms operating in two developing countries: Georgia and the Philippines. Diaspora-owned and diaspora-managed firms are better connected than other foreign firms and they use social ties to resolve disputes and influence government policy. At the same time, Graham shows that diaspora-affiliated firms are no more socially responsible than their purely foreign peers—at root, they are profit-seeking enterprises, not development NGOs. Graham identifies implications for policymakers seeking to capture the development potential of diaspora investment and for managers of multinational firms who want to harness diasporans as a source of sustained competitive advantage.

This paper reviews common challenges faced by researchers interested in measuring the impact of migration and remittances on income, poverty, inequality, and human capital (or, in general, "welfare") as well as difficulties confronting development practitioners in converting this research into policy advice. On the analytical side, the paper discusses the proper formulation of a research question, the choice of the analytical tools, as well as the interpretation of the results in the presence of pervasive endogeneity in all decisions surrounding migration. Particular attention is given to the use of instrumental variables in migration research. On the policy side, the paper argues that the private nature of migration and remittances implies a need to carefully spell out the rationale for interventions. It also notices the lack of good migration data and proper evaluations of migration-related government policies. The paper focuses mainly on microeconomic evidence about international migration, but much of the discussion extends to other settings as well.

This book provides a strong multidisciplinary examination of the links between migration, remittances and sustainable development in Africa. It makes evidence-based policy recommendations on migration to help achieve the Sustainable Development Goals. The key themes examined are migration and remittances, and their relations with the following issues: economic transformation, education and knowledge, corruption and conflict. Cross-cutting issues such as gender equality and youth are weaved throughout the chapters, and a rich range of country contexts are presented. The volume also discusses challenges in managing migration flows. It will be of interest to advanced students, academics and policy makers in development economics and sustainable development.