NO ONE knows better than a social worker that most problems are solved by finding the right answer for the particular difficulty, by joining the two parts of a puzzle. One of the world's greatest social problems today is how new homes and homeless people may be brought together. What are the countries of the world doing to provide refuge for millions of dispossessed men, women, and children? The problem grows constantly more serious and may be expected to increase in gravity for some time to come. Are there areas in the world today which need the kind of workers and settlers which are available? Can nature and man be brought together through human contrivance and wise planning? Migration is an intensely interesting phenomenon as well as one of the most vital of social problems. Man since his creation has been on the move. Whatever the motivation — need of food, greed for loot, search for more temperate climate, desire for room in which to expand, lure of better economic conditions, or escape from social, political, or religious oppression — his course through the centuries has been one of dispersion throughout the world. After the first geographical discoveries North and South America became the mecca both for adventurers and for dissatisfied inhabitants of European countries. The United States soon forged ahead as the principal country of immigration in the New World. The record of immigrants who have come to this country, totaling nearly 40,000,000 individuals, is vividly described as having been, both in volume and in variety, "the most remarkable peaceful mass movement of population in history."2