Migration is as old as humanity itself. But the defining aspect of migration in the 20th and 21st centuries is the complexity and scale of the phenomenon, which has been transformed by increasing globalisation and new transport and communication technologies. The number of international migrants has increased by 41% since 2000, and now stands at 244 million. This equates to 3.3% of the world's population. Some 150 million of these people leave their home countries to find work. Of these migrant workers, around half are women and a third are young people aged between 15 and 34.
There are currently over 65 million displaced people worldwide. They have left their homes due to persecution in their regions of origin or because they have been subjected to situations of serious violence. Of these people, some 28 million are children. The number of child refugees under the mandate of the Office of the UN High Commissioner for Refugees (UNHCR) has doubled in the space of 10 years.
Besides the documented refugees, internally displaced persons and asylum seekers, millions more people are forced to leave their homes involuntarily. Because their situation does not correspond to any internationally recognised category they do not fall under any established legal protection system, such as the 1951 Geneva Convention Relating to the Status of Refugees and its 1967 Protocol. The reasons behind this forced migration include natural disasters and the negative effects of climate change, the consequences of state fragility, systemic poverty and a lack of prospects.