Half a million people are in Spain without official permission.
They come mainly from Colombia, Peru, Honduras, Paraguay, and Argentina. It’s thought that most outstay their work, student, or tourist visas.
An amnesty to grant them legal status to remain and work is due to start within weeks.
It's a very different approach from most other countries in Europe that have been tightening controls on migration.
The prime minister has admitted “Some say we've gone too far, that we're going against the current”.
Opposition parties argue that this policy puts pressure on public services.
This week on The Inquiry, we’re asking: “How will Spain’s migrant amnesty work?”
Contributors: Ismael Gálvez Iniesta, assistant professor, department of applied economics, Universitat de les Illes Balears, Spain Donna Cabrera, independent researcher, international migration lecturer, Pontificia Universidad Javeriana, Colombia Alana Moceri, international relations professor, IE University, Spain Joan Monràs, economics professor, Universitat Pompeu Fabra, Spain
Presenter: Charmaine Cozier Producer: Daniel Rosney Researcher: Evie Yabsley Editor: Tom Bigwood Technical producer: James Bradshaw Production Management: Phoebe Lomas and Liam Morrey