Anti-immigration and ultra-nationalistic politics are rising in Europe, the United States, and across Asia and Africa. Neeraj Kaushal, an economist and professor of social work, investigates the rising anxiety and common complaints, such as whether immigrants replace host-country workers and whether they are a net gain or a net drag on host countries. She finds that immigration, on balance, is beneficial to host countries and shows that today’s global mobility is historically typical; that most immigration occurs through legal frameworks; the U.S. system works quite well most of the time and its features are replicated by many countries; and proposed anti-immigrant measures are likely to cause suffering without deterring potential immigrants.