E/CN.4/2000/82 page 16 institutional obstacle is the failure to achieve widespread ratification of international instruments dealing with migrants’ rights, such as ILO conventions No. 97 and No. 143 and the 1990 International Convention on the Protection of the Rights of All Migrant Workers and Members of Their Families. 78. The vulnerability of migrants is another significant obstacle: human rights abuses related to deportations and inadequate training of officials in human rights matters can be counted as institutional obstacles. 79. Among the social obstacles confronting migrants are social exclusion and the concentration of migrant households in disadvantaged urban areas, which make access to education, health care or employment more difficult. Even more seriously, the social obstacles include segregation and hostility, stereotyping, xenophobia and racism. 80. There are some groups of migrants who hover on the fringes of the documented and undocumented sectors. They include, in the first place, women used for pornography and prostitution; domestic workers, most of whom are women; and farm and seasonal workers, who seem to be particularly vulnerable to rights abuses because of their short-term employment, low educational level and labour legislation that favours agro-business. 81. A large number of countries are unwilling to ratify the human rights standards of the United Nations and ILO. This unwillingness is the result of real people defending real interests with the backing of real power bases - the very people who are often responsible for the obstacles to the full application of these human rights standards. VII. PRELIMINARY CONCLUSIONS 82. Contemporary trends in migrant movements in the era of globalization pose a challenge to the protection of the human rights of that large sector of the world’s population. The first challenge is to define a concept of migrant populations that will cover new situations and to translate that into definitions in the international instruments. The situations referred to are those in which a large number of persons find themselves after leaving their country of origin or even before they do so. Unlike refugees, these populations have no formal status that affords them international protection. In many cases, these same groups and individuals do not fit into the category of migrant worker. This shortcoming in terms of definitions is all the more serious if we bear in mind that well-founded field studies show that more and more of today’s migrants are women on whom there are no data. 83. The phenomenon of women migrants is a sign of the growing participation of women in remunerated productive activities. The same phenomenon is also a manifestation of a change in the social fabric, the main feature of which is the increase in the number of households headed by women. In many cases, the new family situation arises when the father migrates or leaves his family.