The World Bank has usefully assembled in one place what is known (and can plausibly be guessed) about intercountry migration in the world and the flows of remittances that result. One hundred ninety-one million people, three percent of the world's population, were living in countries other than their countries of birth in 2005; seven percent of them were refugees. They sent nearly $300 billion in remittances, presumably to their countries of origin. Some salient facts: most countries have both immigrants and emigrants; indeed, five of the top ten countries in terms of immigration -- Germany, India, Russia, Ukraine, and the United Kingdom -- are also among the top ten countries in terms of emigration. Nearly as much migration occurs between developing countries as from poor to rich countries. The United States has the largest number of immigrants, but when immigrants are considered as a share of the population, the United States is exceeded by the oil-exporting Gulf Arab countries and by Australia, Canada, and Switzerland (with Germany, Spain, and Sweden not far behind). The densest migration corridor is from Mexico to the United States, followed by Russia-Ukraine and Bangladesh-India. Over 30 small countries lose over one-third of their college-trained citizens through emigration. The United States is the largest source of remittances, followed by Saudi Arabia and Switzerland. Altogether, this volume is a handy and interesting source of information. Meanwhile, intracountry migration, about which information is harder to get, is undoubtedly much higher than intercountry migration; migration within China alone probably matches the global total for migration between countries.