Migration has always been a part of human life. Whether we consider ourselves the descendants of different cultures that developed parallel to one another or, as the most recent research indicates, we come from a small group of Africans who first left Africa some 100,000 years ago, migration has characterized the behavior of humans for centuries. Today, however, we are no longer nomadic hunters and gatherers. Now, nation states attempt to control how and where people move. Although migration has been a constant for most of human history, social scientists have observed that since World War II the movement of people around the globe has intensified in proportions that have surpassed earlier population movements (Friedman, 2006).

In fact, social scientists have called the post-World War II movement of people around the globe "the age of migration." As a collective, of analyses defies the simple characterization of migration as a choice of people seeking better income opportunities. They do so by challenging us to be attentive to the specific historical context that frames the migratory movements depicted in each country. I have been sensitive not only to the ways that race, class, and gender dynamics influence the composition of migratory flows, but also to the reasons why people migrate and the outcomes of population movements.

Scholars challenge us to reconsider our notions and, in some cases, stereotypes of the "traditional" actors involved in the process of migration. They draw out the human cost of migration for the people involved through carefully selected personal vignettes that alert us to the new conditions and forces that shape the complex processes of contemporary migratory movements. While the global mixing of the world's peoples continues to accelerate in the twenty-first century, it is likely that this process is still in its infancy. ?ighteenth-century German and Irish migration to North America pointed the way to the mass transoceanic migrations of the nineteenth century.

In an even larger canvas, the ethnic composition of free and coerced migration in the four centuries before 1900 is a template for migration in the twentieth and twentyfirst centuries. No one who has taken a subway ride in New York, London, or Toronto can be in any doubt that modernity today is increasingly associated with the multi-ethnic metropolis, despite government efforts to control migration from the developing world. In the last two decades four-fifths of all US immigrants have originated from non-?uropean parts of the world, and the equivalent ratios for most ?uropean countries are only slightly smaller. In London today, there are no less than 307 languages spoken by the 25 percent of the city's children who use a language other than ?nglish at home.

In Amsterdam the figure is 180, and the New York figure is unlikely to be smaller than London's. (Friedman, 2006) A multi-ethnic supply of labor appears far more important to the continuation of the modern global economy than to its seventeenth- and eighteenth-century rise. ...