Since its beginning in September 2004, the negotiation of the Convention on the Protection and Promotion of the Diversity of Cultural Expressions has raised a great deal of interest and even tension among UNESCO member states. A record number of members and non-governmental observers have been involved, and, on many occasions, the debates have taken place in overflowing rooms. During the study of the draft convention by Commission IV, on 77 October 2005, the debate even had to be temporarily suspended in order to find a larger room. Obviously, the negotiations, which addressed head on the problem of the interface between trade and culture, dealt with a very sensitive matter. On 20 October 2005, the convention was finally adopted by the UNESCO General Conference (148 votes for, two against, and four abstentions). Considered to be a historical moment by several delegations in their closing declaration, the results of this decision was vigorously denounced by the United States. It went so far as to assert, in a declaration made public by the US embassy in Paris, that the proposed convention was deeply flawed since it dealt with trade rather than culture and that it therefore fell outside UNESCO jurisdiction. How was such a result achieved? This article attempts to clarify these issues, following the negotiation step by step as well as the dynamic that led to the ultimate result.