One of the most dangerous causes of international friction is the denial of the right of migration. If present trends continue, and prophecy is becoming more confident as statistics improve, Germany's population will begin to decline within one decade, Italy's within two, and Japan's within four. Psychological and political changes are less calculable, but at least it may be hoped that a wise and generous handling, deliberately undertaken in good time, could settle the problem, and not lead (as some fear) to an endless series of new demands. Some say that Italy and Germany have no right to ask for more "room to live" because they are trying to increase their populations by various forms of state action, premiums on marriage and the encouragement of large families. The International Labour Organization has published a number of studies on openings for colonization, and on the best methods of settlement to be adopted.