Migration movements are a manifestation of social mobility on a horizontal level, and are basically typified in the general classification of intercontinental, continental, and intranational migrations. They may be studied under three different perspectives: quantity or number and type of migrants; integration in the host-society; policies favoring integration and the organiza? tions determining and influencing them. In the last ten years, in particular, the attention of sociologists was directed to studying the nature and the meaning of the integration of mi? grants. The existence of problems in the process of socio-cultural adjustment is realized by all scholars, but differences arise in the interpretation of such problems. For C. F. Ware, the problem is in the socio-economic situation of the host-society. For R. Clemens, it is the change in immigrants* behavior due both to the passage from one country to another and from agriculture to in? dustry. For Eisenstadt, it is the change of social roles. A variety of opinions is also found in the way of conceiving migrant integration: complete conformity to the national way of life of the immigration country; complete self-identification and preservation of the immigrant group in the new society; cultural pluralism, /. e. acceptance of the fundamental values of the host-society and at the same time preservation of the immigrant culture as far as it is not an obstacle to the socio-cultural balance of the new environment. The last view, most common today, was espoused by the assemblies of The International Union for the Scientific Study of Population (Geneva 1949) and by the UNESCO Conference held in Havana in 1956 that dealt with the problem of the cultural integration of immigrants. In the field of terminology, assimilation is very often used to describe migrants* integration, but with varying meanings. Diufelait intends assimila? tion as complete conformity. H. Bunle, G. Mauco, J. Isaac, Clemens consider assimilation in the general sense of breaking down the barriers of behavioral identification between immigrants and natives, although each writer maintains a different degree of interpretation of the term. Other scholars use assimila-