A/60/357 I. Introduction 1. At its fifty-fifth session, the Commission on Human Rights, decided, in resolution 1999/44 of 27 April 1999, to appoint for a three-year period a special rapporteur on the human rights of migrants to examine ways and means to overcome the obstacles existing to the full and effective protection of the human rights of this vulnerable group, including obstacles and difficulties for the return of migrants who are non-documented or in an irregular situation. 2. In accordance with that resolution, since 1999 the Special Rapporteur has submitted six reports to the Commission on Human Rights and two interim reports to the General Assembly. 3. In a letter dated 29 July 2005, the Chairperson of the Commission on Human Rights at its sixty-first session appointed me Special Rapporteur on the human rights of migrants. I should like to take this opportunity to express my gratitude to Ms. Gabriela Rodríguez Pizarro for her major contribution to the question of the human rights of migrants from 1999 to 2005. 4. This report is submitted in accordance with General Assembly resolution 59/194 and Commission on Human Rights resolution 2005/47. I officially assumed the mandate on the question of the human rights of migrants on 3 August 2005 and in this report, therefore, I shall limit myself to some preliminary observations, which will be developed further in my next report to the Commission. II. Preliminary observations 5. International migration is a growing phenomenon because it is linked to globalization. That growth can be measured by the increased trade in goods and services between nations, which in turn cannot be maintained without flows of migrants and of the information and ideas which motivate them to cross borders. The increasing attention being paid by Governments to the phenomenon of international migration may be attributed to the growth in the numbers of migrants but that attention has not been matched by equal treatment in terms of their human rights. The General Assembly decided to respond to the obvious and continuing deterioration in the treatment of migrants by designating international migrants as a vulnerable group. That designation not only focused special attention on the part of the Organization to that group but also facilitated analysis of the root cause of the problem and possible solutions. If the concept of vulnerability is defined as meaning that migrants, by the very fact of being migrants, are disadvantaged with regard to the other members of their host society, which defines them as such, their situation may be described as a situation of legal and social inequality which makes a distinction between nationals and aliens. That distinction is generally considered to be one of the most important acts of sovereignty, warranting inclusion in the Constitution as one of the fundamental elements defining the nation. The definition of who is or is not a national not only defines the community to which national sovereignty is entrusted, but also establishes a criterion which becomes a source of inequality between nationals and non-nationals, in other words, aliens. 6. This conceptual context leads us to the question of the juridical and social nature of the relations in practice between those who are constitutionally defined as nationals, and aliens. There are many possible responses. As Special Rapporteur of 2