; ˈɡastˌʔaʁbaɪtɐ; both singular and plural) are foreign or migrant workers, particularly those who had moved to West Germany between 1955 and 1973, seeking work as part of a formal guest worker program (Gastarbeiterprogramm). As a result, guestworkers are generally considered temporary migrants because their residency in the country of immigration is not yet determined to be permanent. Other countries had similar programs: in the Netherlands and Belgium it was called the gastarbeider program; in Sweden, Denmark, Norway and Finland it was called arbetskraftsinvandring (workforce-immigration); and in East Germany such workers were called Vertragsarbeiter. The term that was used during the Nazi era was Fremdarbeiter (German for 'foreign worker'). However, the latter term had negative connotations, and was no longer used after World War II.
The term is widely used in Russia (гастарбайтер, gastarbayter) to refer to foreign workers from post-USSR or third-world countries.
Following World War II there were severe labour shortages in continental northern Europe, and high unemployment in southern European countries including Turkey.
During the 1950s and 1960s, West Germany signed bilateral recruitment agreements with a number of countries: Italy (22 November 1955), Spain (29 March 1960), Greece (30 March 1960), Turkey (30 October 1961), Morocco (21 June 1963), South Korea (16 December 1963), Portugal (17 March 1964), Tunisia (18 October 1965), and Yugoslavia (12 October 1968). These agreements allowed the recruitment of guest workers to work in the industrial sector in jobs that required few qualifications.
There were several justifications for these arrangements. Firstly, during the 1950s, Germany experienced a so-called Wirtschaftswunder or "economic miracle" and needed laborers. The labour shortage was made more acute after the building of the Berlin Wall in August 1961, which drastically reduced the large-scale flow of East German workers. Secondly, West Germany justified these programs as a form of developmental aid.