SUMMARY Throughout the world, international migrations flow from poor countries to industrialized ones. Because of difference in wage levels and working-conditions, migratory pressures are strong; this makes the application of laws protecting national labour very difficult and leads to illegal migration and irregular situations. There is a trade in human lives which gives rise to cruelties. It is impossible to give a global account of illegal immigration throughout the world, but the phenomenon exists in several countries where there is immigration, especially in France and the U.S.A. The situation is further confused by a change in the attitude traditionally adopted by public opinion and trade unions. For various reasons, but mainly becaus...