A disagreement between Michel Andrault and Pierre Parat led to the duo splitting up. In 1995, Andrault continued his work at La Défense, teaming up with Nicolas Ayoub. This partnership resulted in a change of style for the Belvédère. Compact and combining stone and glass, the two buildings marking the entrance to the Valmy district, behind the Grande Arche, are no more than nine stories high.

Their shapes echo both Spreckelsen's monumental cube and the tapered lines of the Pacific Tower. Designed as a square, the semi-circular patio brings all the workspaces together. The exterior facades reveal a discreet attic floor that nevertheless conceals the complexity of the building, namely the span over the circular boulevard.

In July 2016, Paris La Défense signed an agreement with VINCI Immobilier authorizing the operator to substantially restructure the Belvédère building and create additional space as part of its work.

Ideally located in La Défense in the Valmy district, at the foot of the Grande Arche and the Cœur Transport multimodal hub, the building is also part of the Jardins de l'Arche sector, a new leisure and cultural destination in Paris La Défense.

The property developer entrusted architect Axel Schoenert with the task of reinventing the building. He designed the future façades to create an optical effect based on lines that will connect the different spaces of the building and help convey a very contemporary image.

Following the completion of the work in 2018, the building, which is not subject to high-rise building regulations, now offers 18,000 m² of office space. Highly flexible, it will offer large floor plates of over 1,600 m², a large terrace, and a landscaped roof terrace. A retail space created at the foot of the building completes the range of services offered in this very dynamic neighborhood.

Le Belvédère was the first building in La Défense to offer the “Open Work” concept developed by VINCI Immobilier, a new office solution adapted to changes in the use of workspaces. It should be noted that the creation of the space required for the launch of Open Work was the result of a sale between Paris La Défense and VINCI Immobilier.

It was in 1995 that Agence Conceptua, founded by Michel Andrault (1926) and Nicolas Ayoub, made its debut in La Défense. The two architects, one a leading figure in French architecture known for having designed several master plans for the business district and the other co-designer of the Société Générale towers in 1995, launched their first project: the KPMG building (now Le Belvédère).

They then focused on the main buildings in the Faubourg de l'Arche district: the Cèdre tower, the Égée tower, and the Adria tower.