The Michelet-Gan Groupama complex, along with Coface and Athocem, was the first major architectural development of the 1980s. The master plan for the Michelet district in the 1970s called for the construction of 400 housing units in several buildings connected to the slab. However, the project was abandoned due to the oil crisis. Development of the site remained on hold for several years.

However, the project was taken up by Michel Andrault and Pierre Parat, who had recently arrived in the business district. It took the form of different volumes playing with the silver and black colors of the facade frames and glazing.

The gardens of the interior patios can be seen from the Esplanade through large porches.

Michel Andrault (1926) and Pierre Parat (1928) joined forces in 1957 and occupied a prominent place on the French architectural scene for nearly forty years. Known for their work on housing (the Pyramides d'Epernay and Evry), they also designed major facilities such as the Palais Omnisports de Paris-Bercy.

In 1985, they entered La Défense and, like Henry La Fonta, established themselves as the most influential architects on the site. They accompanied its transformation for nearly ten years and designed several master plans. In terms of achievements, Michel Andrault and Pierre Parat participated in a dozen projects, including the restructuring of the CNIT and the Société Générale towers. In 1997, the Renaissance Hotel marked their last collaboration. Michel Andrault then continued his career by founding the Conceptua agency with Nicolas Ayoub.