Vimont's first post was at the French embassy in London, where he served as second secretary from 1977 to 1978 and first secretary from 1978 to 1981. He then served at the Press and Information department in Paris from 1981 to 1985. From 1985 to 1986 he worked at the
EastWest Institute in
New York City. Then he moved back to Europe to become the second councillor at the Permanent Representation of France at the
European Community in
Brussels, from 1986 to 1990. Vimont subsequently became chief of staff to successive ministers delegate of European affairs
Édith Cresson and
Élisabeth Guigou from 1990 to 1993. He was the director for development and of scientific, technical, and educational cooperation (1993–1996) and subsequently the adjunct general director of cultural, scientific, and technical relations (1996–1997), and the director of European cooperation (1997–1999). From 1999 to 2002 he was the ambassador and permanent representative of France at the European Union in Brussels. From 2002 to 2007 he served as chief of staff to three French Foreign Ministers,
Dominique de Villepin (2002–2004),
Michel Barnier (2004–2005) and
Philippe Douste-Blazy (2005–2007). In 2007,
President Nicolas Sarkozy appointed Vimont to the position of
Ambassador to the United States. On 6 November 2007, he was among the guests invited to the
state dinner hosted by U.S. President
George W. Bush in honor of Sarkozy at the
White House. On 25 October 2010, Vimont was selected by the
European Union's (EU)
High Representative Catherine Ashton to be the first Executive Secretary General of the
European External Action Service, which began operation on 1 December 2010. ==Later career==