The specificity of the Nanterre project lies in the fact that it brings together two programmes, each of which welcomes different audiences: the District of semi-freedom (QSL) and the headquarters of the Penitentiary Services of Insertion and Probation of the Hauts-de-Seine (SPIP).

The first strong concept was to make the QSL a resolutely urban object. It is a work on the limit that guided a deep reflection on the evolution of a typology with little experience in mixed and densely populated contexts.

In Nanterre, the building encloses the plot. The fence is thought out in thickness, disappearing and becoming an inhabited wall. The complexity of the programme and the compactness sought make it necessary to think together to optimise the interweaving of the programmes and their perfect sealing enclosure. The resulting simple and monolithic form is in fact a thick wall that organises the strictly differentiated management of the plurality of routes: prisoners, prison and administrative staff, visitors. The centre of the plot is dedicated to the life of the inmates: the 90 individual cells, the garden, the courtyard and the sports fields.

From the street: a monolith with a large window, from the inside: a white, mineral box, open to the sky and the Ile-de-France skyline. The metaphorical dimension of the building explores a dual symbolism of justice: the authority of a mass of steel and the promise of a horizon.

This attention to the environment of the prisoners takes note of the everydayness of their uses. Life in semi-liberty calls for a rethinking of the comfort of the cell, not in terms of its standard dimensions or secure access, but in terms of its relationship to the outside world: orientations, views, outdoor spaces, planting, etc., in order to work on society's imagination of the prison and security.