Controlling immigration has always stood at the forefront, whereby new issues, such as integration, have only gradually been given more room in the debate. In terms of the evolution of migration policy in Spain, it is possible to differentiate between three or four phases.
In the initial policy development phase, basic legal provisions were created, and political awareness concerning immigration developed. Among these basic provisions were the articles pertaining to foreigners and asylum that were included in the 1978 constitution as well as the more restrictive and police-oriented Aliens Act of 1985. This law was generated at a time when there was no significant immigration to Spain. At the time, migration-related issues played no role in parliamentary discussion. Only as the implementation of such regulations proved problematic, as demonstrated at the end of the 1980s, did lawyers, non-governmental organisations and the Defensor del Pueblo (ombudsman) begin to address the topic.
The political realisation that immigration-related problems actually existed led the government to formulate a baseline for immigration policy in 1990. This political programme laid the foundation for the second phase of migration policy-making in Spain, a phase characterised by differentiation, coalescence and consolidation. Regulations were introduced that affected all areas of migration policy: entry and visa regulations, expanded border security, the introduction of permanent work permits, quotas for foreign workers and a tighter asylum policy in line with harmonised European regulations. Also, initial steps were taken toward creating an integration policy, including the adoption of permanent residence permits and regulations for reuniting families as well as the creation and expansion of specialised administrative services. One of the most important political measures during this phase was the adoption of new regulations concerning the implementation of the Aliens Act of 1996, which encompassed many of the above-mentioned regulations. Overall, this development was influenced by the gradual emergence of a European migration policy, especially by Spain's 1991 entry into the Schengen agreement, which brought with it a significant number of obligations.
The third phase of migration policy development in Spain began in 2000, as the "Law Concerning the Rights and Freedoms of Foreigners and their Social Integration" (Ley Orgánica 4/2000) took effect. This law can be considered as modern, flexible migration legislation, designed to facilitate legal immigration and social integration while retaining all existing control mechanisms. With the recognition that immigration would remain a constant, Spain had emerged as a true immigration country. Immigration had gone from being a neglected issue to a key political one. Thus the topic found its way into the centre of political debate and increasingly became a populist tool for political mobilisation. After winning an absolute majority during the March 2000 election, the governing conservative People's Party (Partido Popular; PP) tightened the law (Ley Orgánica 8/2000) in order to, among other things, prevent undocumented immigrants from enjoying various rights afforded to persons with a valid residence permit. The restrictive direction of migration policy under the PP led to stricter measures regarding deportation, internment and family reunification, as well as to penalties for aiding and abetting illegal immigration.
The change of government following the elections in March 2004 brought with it a new phase of legal stability in which the question of foreign integration clearly eclipsed the question of safety and control, as evidenced by the movement of the public body in charge from the Ministry of the Interior to the Ministry of Labour and Social Affairs. The new socialist government took a liberal, consensus-oriented approach to the issue of immigration. While the law has remained unchanged, the new regulations on implementation passed at the end of 2004 were significantly more liberal in nature.