Given the huge worldwide demand for migration from underdeveloped countries to the developed countries, particularly the United States, a prima facie case can be made that migration probably benefits the migrants a lot. The case can be made in two ways:

• Stated and revealed preferences of migrants and potential migrants looks at what migrants and potential migrants themselves say and do.
• Concrete benefits to migrants tries to use various quantitative and qualitative indicators to judge whether migrants are better off after migration compared to before migration, and the extent of the difference in their condition.