The conclusion of an agreement between the different political formations claiming they belong to the left and the ecologist movements with the view of the coming parliamentary elections make us inevitably thinking to the Seventies alliances between the left parties and to the Common Program. They were going to lead to the François Mitterrand election 1981 May 10th, followed by a large victory in the parliamentary elections some weeks later. A similar alliance in 1997 will allow the “plural left” to winning the parliamentary elections and to constraining Jacques Chirac to nominate Lionel Jospin Prime minister. The cohabitation ...