Stéphane Dion (stāfän´ dyôn), 1955–, Canadian politician, b. Quebec, grad. Laval Univ., Quebec (B.A. 1977, M.A. 1979), Institut d'études politiques, Paris. A political science professor at the Univ. of Moncton, N.B. (1984), and the Univ. of Montreal (1984–96), he was first elected to the Canadian parliament, as a Liberal, in 1996. He served as minister of intergovernmental affairs (1996–2003) and minister of the environment (2004–6) under Jean Chrétien and Paul Martin, respectively. Following the Liberal party's defeat in the 2006 elections, Martin resigned as party leader, and Dion, who was not favored to succeed him, was nonetheless elected to the post. Under Dion the party lost additional seats in the 2008 elections, and when he later resigned Michael Ignatieff became interim party leader. Dion is noted as the author of the Clarity Act (2000), which set precise and strict terms for any future move to establish independence for Quebec.