Stéphane Dion, Canadian sociologist and politician, 15th Canadian Minister of the Environment
Stéphane Maurice Dion (born 28 September 1955) is a Canadian diplomat, academic and former politician who has been the Canadian ambassador to Germany and special envoy to the European Union since 2017. Dion was Leader of the Opposition and the leader of the Liberal Party from 2006 to 2008. He served in cabinets as intergovernmental affairs minister (1996–2003), environment minister (2003–2006), and foreign affairs minister (2015–2017).

Before entering politics, Dion was a professor of political science at the Université de Montréal. His research focused on Canadian federalism and public administration. Throughout his tenure in government, Dion held a number of portfolios. He was first named Minister of Intergovernmental Affairs by Prime Minister Chrétien in 1996, following the aftermath of the 1995 Quebec sovereignty referendum. His reference question to the Supreme Court of Canada, produced Reference Re Secession of Quebec and his Clarity Act, which provided guidelines for subsequent referenda. He returned to the backbench in 2003 when Paul Martin became the prime minister and dropped a number of ministers in an effort to disassociate himself from the former Chrétien government. After the 2004 election however, he returned to Cabinet as Minister of Environment, where he was in charge of implementing the Kyoto Protocol and chaired COP 11/CMP 1 when Montreal hosted the UN climate conference in 2005. The Liberal government lost the 2006 election and Martin resigned as leader. Dion campaigned to replace him and subsequently won the party leadership election. Dion ran on an environmental platform in the 2008 federal election, but was defeated by Prime Minister Stephen Harper, only managing to return the party to Official Opposition. After a subsequent parliamentary dispute, he was replaced as Liberal leader by Michael Ignatieff. He continued to sit as the member of Parliament (MP) for Saint-Laurent. In 2015, the Liberal Party returned to power and Dion was named to Justin Trudeau's Cabinet, serving until 2017, when he left politics and assumed his current diplomatic postings.