This article illustrates how the Acadian community in Nova Scotia took advantage of the 3^rd World Acadian Congress held in the province in 2004 to demonstrate its economic potential and thus advance political, socioeconomomical and cultural priorities. It will draw from the case of Baie Sainte-Marie, one of the host regions of the Congress, to show how the preparations leading to the event participated in promoting the use of French in the development of a tourism industry which puts forth linguistic authenticity. In this industry, acadjonne – a set of language practices to which a large part of the community identifies itself – becomes a prime stamp of authenticity, but also gains in legitimacy before other francophones. This study draws on ethnographic fieldwork conducted in three stages between 1999 and 2004, and mainly on interviews with social actors from Baie Sainte-Marie, with board members of the 3^rd World Acadian Congress, and with actors from the main organizations supporting the Acadian tourism industry.