Of the 232 million international migrants counted by the UN worldwide, 35 million are under 20, and 40 million more are between 20 and 29 years old. But this does not reflect the weight of young people in international migration flows: 46% of the roughly 4 million new migrants registered every year are between 15 and 30 years old, and new immigrants are notably younger than local populations. One cannot ignore the fact that international youth migration is a marginal phenomenon in comparison to the figures for internal (mainly rural-urban) youth migration—according to the World Youth Report 2013, published by the United Nations on the 14^th February 2014, the latter may amount to 740 million people worldwide. They change country or region in search of better (mainly economic) prospects, or in flight from economic or political distress at home. The stereotype of young people from developing countries flooding into the rich North is far from accurate: an estimated 60% of youth international migrants are living in developing countries, and among young people South-South migration is more common than South-North migration.

It is, however, in developed countries that youth immigrants make a big difference: in 2013 youth immigrants accounted for 9.1% of the total youth population in developed countries, against only 1.4% of the youth population in developing countries; as this is an average, in many urban areas in developed countries this percentage easily exceeds 20% or even 30%. So in developed countries youth policy can no longer be conceived without taking into account the specific challenges of youth immigrants and the transformations they are bringing about in the host societies.

Youth Left Behind. But the analysis of youth international migration should not stop at youth migrants themselves. Youths and children left behind by migrant parents are also direct stakeholders in international migration. Their psychological and social development and education patterns, health conditions and even entrepreneurial capabilities are directly affected by migration in their families, the remittances and hence better opportunities that they receive, and the wider prospects they enjoy.

Youth Aspiring to Migrate. The impact of international migration is felt well beyond the migrants and their families. In many developing countries, and particularly those neighbouring rich countries (Southern Mediterranean or Easter European Countries, Mexico and Central America, South Asia), a large proportion of the youth dreams of migration as a life project of choice. But this does not necessarily mean that they are planning to do it in the short term or are actively preparing migration or even that they have a high probability of migration. A 2011 Gallup World Poll carried out in 146 countries and cited in the above-mentioned UN report estimated the number of individuals dreaming of permanently leaving their countries at a staggering 630 million. However, of that total, only 48 million were planning to move within the coming year, and only 19 million were actively preparing to emigrate. However, this is still a fairly impressive figure, and the mere possibility of migration determines the social behaviour of many more.

For the countries of origin of international migrants, youth policy—including, in a broad sense, education and training policy, youth employment policy and territorial development policy—cannot be effectively designed and implemented without taking into account the reality and prospects of international migration of their young people.