Changes in the national-origins quota system, the preference system, labor certification and adjustment-of-status provisions led to changes in the size and composition of immigration. Within a context of increasing size and changing area of origin, the proportion of immigrants with a stated occupation increased, and the occupational composition of total immigration and of immigration by continent of origin changed. Europe and the Americas generally switched to lower-skilled levels, and Asia, Africa and Oceania, to white-collar, especially professional, levels. The composition of occupational groups also changed, with Asia generally increasing its contribution and most noticeably so in the professional group. Adjustment of status has generally increased, but it has not become mainly a subterfuge for foreign students and exchange visitors to remain in the country. Relatives and refugees dominate the adjustee group.