Suez S.A., known from 1997 to 2001 as Suez-Lyonnaise des eaux, was a leading French multinational corporation headquartered in the 8th arrondissement of Paris, with operations primarily in water, electricity and natural gas supply, and waste management. Suez was the result of a 1997 merger between the Compagnie de Suez and , a leading French water company. In the early 2000s Suez also owned some media and telecommunications assets, but later divested them. According to the Masons Water Yearbook 2004/5, Suez served 117.4 million people around the world. The company conducted a merger of equals with fellow utility company Gaz de France on 22 July 2008 to form GDF Suez (called Engie since 2015). The water and waste assets of Suez were spun off into a separate publicly traded company, Suez Environnement. The revenue of GDF was around 22.4 billion euros in 2005, compared to 41.5 billion for Suez. The CGT trade-union called the merger a "disguised privatization."
On 3 September 2007, Gaz de France and Suez announced agreed terms of merger. The deal was conducted on the basis of an exchange of 21 Gaz de France shares for 22 Suez shares via the absorption of Suez by Gaz de France. The French state holds more than 35% of shares of the merged company, GDF Suez. As a consequence of the conditions posed by the European Commission with regards to allowing the merger, on 29 May 2008 Suez sold its Belgian gas supplier Distrigas to the Italian company Eni for €2.7 billion. On 22 July 2008 the group GDF Suez, a company of €74 billion of annual turnover, was officially created.