A foreign worker or guest worker is a human who works in a country other than the one of which he or she is a citizen. Some foreign workers are using a guest worker program in a country with more preferred job prospects than their home country. Guest workers are often either sent or invited to work outside their home country, or have acquired a job before they left their home country, whereas migrant workers often leave their home country without having a specific job at hand. A foreign worker or guest worker is a human who works in a country other than the one of which he or she is a citizen. Some foreign workers are using a guest worker program in a country with more preferred job prospects than their home country. Guest workers are often either sent or invited to work outside their home country, or have acquired a job before they left their home country, whereas migrant workers often leave their home country without having a specific job at hand. Tens of millions of people around the world live their lives as foreign workers. An estimated 14 million foreign workers live in the United States, which draws most of its immigrants from Mexico, including 4 or 5 million undocumented workers. It is estimated that around 5 million foreign workers live in Northwestern Europe, half a million in Japan, and around 5 million in Saudi Arabia. A comparable number of dependents are accompanying international workers. Foreign nationals are accepted into Canada on a temporary basis if they have a student visa, are seeking asylum, or under special permits. The largest category however is called the Temporary Foreign Worker Program (TFWP), under which workers are brought to Canada by their employers for specific jobs. In 2006, there were a total of 265,000 foreign workers in Canada. Amongst those of working age, there was a 118% increase from 1996. By 2008, the intake of non-permanent immigrants (399,523, the majority of whom are TFWs), had overtaken the intake of permanent immigrants (247,243). In order to hire foreign workers, Canadian employers must acquire a Labour Market Impact Assessment administered by Employment and Social Development Canada. . Green card workers are individuals who have requested and received legal permanent residence in the United States from the government and who intend to work in the United States on a permanent basis. The United States’ Diversity Immigrant Visa (DV) Lottery program authorizes up to 50,000 immigrant visas to be granted each year. This help facilitate foreign nationals with low rates of immigration to the United States a chance to participate in a random drawing for the possibility of obtaining an immigration visa. In Nazi Germany, from 1940–42, Organization Todt began its reliance on guest workers, military internees, Zivilarbeiter (civilian workers), Ostarbeiter (Eastern workers) and Hilfswillige ('volunteer') POW workers. The great migration phase of labor migrants in the 20th century began in Germany during the 1950s, as the sovereign Germany since 1955 due to repeated pressure from NATO partners yielded to the request for closure of the so-called 'Anwerbe' Agreement (German: Anwerbeabkommen).The initial plan was a rotation principle: a temporary stay (usually two to three years), followed by a return to their homeland. The rotation principle proved inefficient for the industry, because the experienced workers were constantly replaced by inexperienced ones. The companies asked for legislation to extend the residence permits.Many of these foreign workers were followed by their families in the following period and stayed forever. Until the 1970s, more than four million migrant workers and their families came to Germany like this, mainly from the Mediterranean countries of Italy, Spain, the former Yugoslavia, Greece and Turkey.Since about 1990, came for the disintegration of the Soviet bloc and the enlargement of the European Union and guest workers from Eastern Europe to Western EuropeSometimes, a host country sets up a program in order to invite guest workers, as did the Federal Republic of Germany from 1955 until 1973, when over one million guest workers (German: Gastarbeiter) arrived, mostly from Italy, Spain and Turkey. The underestimation of the required integration services by the state and the society of the host countries, but also by the migrants themselves. Switzerland's transformation into a country of immigration was not until after the accelerated industrialization in the second half of the 19th century. Switzerland was no longer a purely rural Alpine area but became a European vanguard in various industries at that time, first of textile, later also the mechanical and chemical industries. Since the middle of the 19th century especially German academics, self-employed and craftsmen, but also Italians, who found a job in science, industry, construction and infrastructure construction migrated to Switzerland. In Asia, some countries in East and Southeast Asia offer workers. Their destinations include Japan, South Korea, Hong Kong, Taiwan, Singapore, Brunei and Malaysia. In 1973, an oil boom in the Persian Gulf region (UAE, Oman, Saudi Arabia, Qatar, Kuwait, and Bahrain, which comprise the Gulf Cooperation Council), created an unprecedented demand for labor in the oil, construction and industrial sectors. Development demanded a labor force. This demand was met by foreign workers, primarily those from the Arab states, with a later shift to those from Asia-Pacific countries. A rise in the standards of living for citizens of Middle Eastern countries also created a demand for domestic workers in the home.