The political use of informal settlements as a reserve of undesirability: displacement, confinement and informality in Madrid

In the 2010s, more than 10,000 people were still living in informal settlements in Madrid while clearance and rehousing policies had been implemented since the 1960s. This persistence is due to the fact that the policies have always been selective, combining instruments for filtering the populations accepted for rehousing and evicting those considered unsuitable. This article shows that informal settlements have been made governable by (re)creating and (re)shaping zones of informality which ensure a role of reserve of undesirability through displacement, confinement and informalization of informal settlements dwellers: to make rehousing and social policies viable in the city centre, regional policies have relied on spaces of confinement at the margins of the city which have ensured the role of hosting, channelling and controlling the most marginal population built as a 'surplus'. The article combines a historical political sociology perspective using archives and statistical analysis to explain the institutionalization of the policies and their socio-spatial effects on the long term. A multi-situated ethnography is also used to investigate the governance of informal settlements policies and their socio-spatial effects in the 2010s.