Within the scope of a PPP (public-private partnership), Bouygues Construction is in charge of the design and construction of La Seine Musicale. This new cultural centre, commissioned by the Hauts-de-Seine Departmental Council and designed by architect Shigeru Ban, includes a large 6,000-seat modular concert hall with capacity for three shows a day, an auditorium with 1,100 places designed for classical music, a singing school, an orchestra in residence and recording studios. The goal: establish a new standard for music centres. On 7 December, the solar sail was installed in Boulogne-Billancourt, on the Meudon side of the city. After a series of static tests, the teams successfully carried out their first kinematic tests of the sail. At a height of 45m, this 200-tonne structure moves nearly 5 metres per minute. Although still under construction, it is a unique technical challenge and represents an unrivalled feat. La Seine Musicale is nearing completion. This ground-breaking building should be open to the public from April 2017.