Immigration requirements may involve restrictive quotas and permits. In most countries work permits are required – and where restrictions are in force, such permits may be unobtainable. This often leads to trafficking in and exploitation of immigrants. Immigration restrictions and quotas may be imposed for racial or colour reasons, often under the guise of employment policy. Despite this, the demand for immigrant workers by firms unwilling to apply legally for work permits may be quite high. They may apply for such a permit once the immigrant is working for them (having entered on a temporary tourist visa) or they may prefer to keep him on an illegal basis so that they can pay less in wages. The families of immigrant workers may be refused entry by law but may also be smuggled in, perhaps at a price. Illegal trafficking takes place at great cost to the immigrant and he may also be a prey to extortion afterwards, or imprisonment and deportation if he is discovered by the authorities. The undocumented migrant may be trapped in a position of permanent inequality and is vulnerable to exploitation due to lack of legal protection and being part of a readily recognizable group which constitutes the lower stratum of society.
In 1993, Greek police estimated that Greece had about 400,000 illegal aliens, including about 130,000 Albanians. Other Greek authorities have put the total as high as 600,000, or 6% of the population of 10 million. Many are economic refugees from the former Soviet Union and eastern Europe, Kurds from Turkey and Iraq, Iranians, Pakistanis, Asians and some Africans. Albanians were responsible for 20 murders in 1992, 17 of the 133 murders in 1991, and led all other foreigners in crime statistics. Crimes committed by Albanians rose 185% in 1992 from 1991 (compared with 13% increase for all foreigners), including 150% more robberies and 128% more rapes.
A crippled cargo plane which struck a low-income apartment block in 1993 revealed the previously unknown scale of illegal aliens in the Netherlands. Frustrated in figuring out how many died in 77 destroyed apartments, the authorities offered a residence permit to any illegals living there who would provide notification that they were still alive. About 2,000 applied. It is now estimated that up to 1% of the Netherlands' 5 million people are illegal aliens. At the same time, across a broad front the tolerance for illegal aliens declined markedly.
In 1992, Japan had almost 300,000 foreigners living illegally, a rise of about 35% over 1991. Thais lead, followed by South Koreans, Malaysians, Filipinos and Iranians. Besides day labourer in dirty (kitanai), hard (kitsui) or unsafe (kiken) work, women are lured to work in the sex trade. In the boom period of the 1980s, foreign worker were tolerated and even encouraged; in the 1990s, they are blamed for many ills, some real, some imagined and some for which they are merely convenient scapegoats.