Imagine Lou Dobbs's head exploding when he hears this. But seriously, this will have profound effects on our economy:

Emigration from Mexico to the U.S. dropped 13% in the first quarter of this year compared to the same period last year, with more Mexicans leaving the U.S. than coming in. Indonesian authorities expect 60,000 or more citizens to be sent home from Malaysia, South Korea and other wealthy neighbors this year, as immigrant workers lose their jobs. Tens of thousands of Indians are washing their hands of Dubai as jobs there dry up and work permits expire. And in the U.K., the number of registered workers coming from new European Union member nations like Poland and the Czech Republic dropped 55% in the first quarter of 2009 compared to the same quarter a year earlier.

A growing number of migrants are returning home to places as diverse as Nepal and Tajikistan, while many are deciding not to emigrate to begin with, says Dilip Ratha, an economist and migration expert at the World Bank in Washington, D.C., citing reports from ministries and embassies. Mr. Ratha calls this reverse migration "very new" and "unprecedented."

Such migratory shifts could have profound consequences for developed nations, especially in places where domestic populations aren't growing fast enough to fill jobs or pay for social needs. High-skill immigrants are an important source of tax revenue in some cities, and their kids fill the classrooms of universities and private schools. In the developing world, remittances sent home by migrant workers are also slowing, meaning less income -- and potentially, less growth.

Some analysts question whether the latest migration reversal will outlast the current recession, or turn out to be as big as migration experts predict. Many immigrants have worked hard to establish themselves in their adopted countries and will be unwilling to leave, even if jobs disappear. Others say the trend could be more long-lasting, especially if returning workers help give developing economies a boost or if rich-world economies take many years to recover.

Workers like Mr. González are going home voluntarily, betting that for all the problems back home, their native countries offer better options than the U.S. and Europe. Many developed economies are contracting, but some developing-world countries including China and India are still growing.