[en] The author proposes some analyses and comments about the relationships between experts who have been involved in various conferences and meetings (from Rio de Janeiro in 1992 to Marrakech in 2002) on climate change. He presents the different groups of experts and comments the issues which have been a matter of debate between them for the past fifteen years. For each of these issues, he gives an overview of the expertise status, highlights consensus as well as dissensus. He compares this expertise with the content of political discourses, and then shows which mechanisms led to The Hague failure and to the incomplete Marrakech's compromise