School segregation in Madrid and Catalonia: the data, what has worked, and a radical-centre answer

Two children living a few streets apart in Madrid or Barcelona can grow up in very different schools: one where most classmates' parents went to university, another where most are newly arrived and on low incomes. School segregation is the name for that sorting, and Spain's two biggest regions have the most of it. It matters for social mobility, the first problem on Democracia 21's list for young people, and it matters for the kind of common citizenship Yascha Mounk argues a diverse democracy needs.

The data

Start with the comparison between regions. Using PISA 2015 data, F. Javier Murillo and Cynthia Martínez-Garrido of the Universidad Autónoma de Madrid found that the Comunidad de Madrid had the highest socioeconomic segregation of any Spanish region, across almost the whole income range, with Catalonia second. They linked Madrid's result to its school choice policies, including the single school district.

A 2021 report by EsadeEcPol and Save the Children, Diversidad y libertad, found that Madrid's segregation had grown very markedly, making it the most segregated region in Spain and one of the most segregated in the OECD. It also found that Spain's socioeconomic segregation in primary school was very high by international standards, behind only Turkey and Lithuania.

The most recent picture is better. EsadeEcPol's reading of PISA 2022 finds that socioeconomic segregation fell slightly in Spain and now sits below the OECD average, falling in almost every region since 2018. It remains high in Catalonia and above all in Madrid, which is especially high despite its improvement. Segregation by migrant origin has risen significantly since 2018, and is highest in Catalonia, the Basque Country and Madrid.

What Catalonia did

Catalonia decided to act. On 18 March 2019 it signed a Pact against school segregation with 30 actions and 189 measures, and in February 2021 it approved Decree 11/2021 on admissions. The decree reserves places for pupils with specific educational needs in every public and concertada school, keeps those places open until the end of enrolment and gives town councils a central role.

The Síndic de Greuges, Catalonia's ombudsman, reported on the results in June 2026. Measured with the dissimilarity index, the share of foreign pupils who would have to change school to reach an even spread fell from 43% in 2018–19 to 29% in 2025–26 in primary, and from 35% to 26% in secondary: falls of more than 30% and more than 25%. The share of municipalities with a high index for foreign pupils, above 0.30, dropped from 40.2% to 10.8%. Foreign pupils' presence in concertada schools has doubled, narrowing the gap with public schools.

The Síndic is also frank about the limits. Socioeconomic segregation, measured by pupils flagged as having needs linked to social disadvantage, has moved far less: in primary from 0.41 to 0.39 since 2022–23, and in secondary from 0.33 to 0.31. The improvement comes from more schools sharing the responsibility, while vulnerable pupils remain heavily concentrated in some of them.

What Madrid did

Madrid took the other road. In 2013–14 it made the whole region a single school zone, and its Ley 1/2022 on freedom of educational choice guarantees that families can choose any school regardless of their address, keeping the national admission priorities. The best evaluation of that policy, by Lucas Gortázar, David Mayor and José Montalbán for FEDEA, separates two reforms. The change in admission points in 2012–13, which cut the points for low income and added points for families with a former pupil at the school, raised segregation, by about 3% by parental education and 13% by immigrant status. The single zone itself had a neutral effect once residential segregation is accounted for, although it increased by about 30% the number of pupils assigned to a school outside their district.

That finding cuts against both camps' favourite story. Choice can live alongside mixed schools. Much of the sorting comes from the rules that decide who gets a place when a school is oversubscribed, and from the hidden costs that keep poorer families out of some schools.

A radical-centre answer

Spain has the legal basis. The LOMLOE of 2020 requires the authorities to take the measures needed to prevent segregation for socioeconomic reasons, to set a balanced share of pupils with specific needs in every public and concertada school, and to reserve places for them until enrolment ends.

The left is right that every school paid for with public money must share the responsibility for vulnerable pupils, and Catalonia shows that reserved places applied to public and concertada schools alike work within a few years. The market-liberal tradition is right to defend families' freedom to choose, and the Madrid evidence suggests a wide choice zone is compatible with less segregation if the allocation rules are right.

Our answer combines them in a way neither side usually proposes. Families rank schools freely across their region. When a school has more applicants than places, a central allocation system applies a double reserve of places adjusted to the socioeconomic profile of each area, as EsadeEcPol and Save the Children proposed, and gives extra weight to socioeconomic need in the admission criteria. Concertada schools get enough funding, with inspection, to end the voluntary fees that quietly keep poorer families away. And every region publishes, every year, a segregation index for every town and district, as the Síndic does for Catalonia, with an automatic review of admission zones and reserves wherever the index rises. Madrid could start in the districts where the index is highest and measure the result against similar districts, in the spirit of our proposal for pilots with a control group.

Raghuram Rajan's case for strong communities includes a warning about communities that close themselves off. A school that reflects its whole neighbourhood is where that warning is answered every morning.