When the Théâtre du Maillon moved in 1999 to occupy the former reception pavilion of the Parc des Expositions, the teams discovered a building of great flexibility and generous dimensions. This ideal spatial organisation will initiate the programme for the new theatre. The users - team, artists and spectators - were aware of the potential of the place, and it was a question of exceeding their expectations: by relying on a partition of the void, by developing large capacities and increasing the volumes so that everything could become a stage, by creating "indeterminate spaces" free for appropriation. The typology of the theatre had to be reinvented. Instead of the classical composition of proscenium theatres, the project replaces this with the concept of a porous building composed of free spaces defined by its circulation. The new Théâtre du Maillon thus attempts to redefine the usual boundaries: between the theatre and the city, between the exterior and the interior, between the front and the back of the theatre, between the artists and the public, and between the disciplines. One roof, one floor, and identical facades. Maximum modularity and flexibility. The Maillon is the first theatre designed with the aim of offering a stage adapted to contemporary theatre. The indeterminacy sought by the architecture of Le Maillon thus revives a tradition of French theatre, making a stage of all places, like the theatre of the Jeu de Paume in the 18th century for example.