For Défense Plaza, the Franco-American association has designed a new type of office building. On a plot located on the edge of the circular boulevard, the volume is both cylindrical and cubic in shape. The 12-story building houses an interior garden in its center, forming a landscaped atrium crossed by a footbridge. The offices are arranged on either side of this private “plaza.” The curtain walls of clear glass, anodized aluminum, and granite echo those of the Total Michelet tower.

In 2004, Défense Plaza received the Building of the Year award from the Commercial Real Estate Show.

Founded in 1936 by Louis Skidmore and Nathaniel Owings, later joined by John Merrill, Skidmore, Owings and Merrill is one of the world's leading architectural firms. Known for its ability to combine design excellence with innovative construction, it has designed numerous office buildings, airports, and engineering structures. Its Lever House, built in 1952 in New York, became one of the icons of international modernism. In 2009, the firm designed the world's tallest tower: the Burj Khalifa in Dubai (828 m).

In 1969, it was invited by Epad to act as a consultant for the Fiat Tower, now known as Areva. For the project, it joined forces with French architects Saubot and Jullien. Although the Franco-American duo submitted bids for the EDF and Engie towers, they did not design any more buildings in La Défense until 2004, when Défense Plaza was completed.