In 1988 Sylvie Lucas received a Master's degree in history from the Université des Sciences Humaines (University of Social Sciences) (now the University of Strasbourg) and, in 1989, a Master's degree in political science and administration from the College of Europe in Bruges, Belgium. From 1990 to 1995 she worked at the Luxembourg Ministry of Foreign Affairs, first for a year in the Department of Political and Cultural Affairs, and then in the Department of International Relations and Economic Affairs. From 1995 to 2000 she was the deputy permanent representative of Luxembourg to the United Nations. She then returned to the Department of Political Affairs as deputy director from 2000 to 2003.
In 2003, Sylvie Lucas became Luxembourg's ambassador to Portugal and Cape Verde, In 2004 she again returned to the Department of Political Affairs, this time as director. On 25 August 2008, ambassador Lucas became the United Nations' permanent representative from Luxembourg. In September 2008 she was elected vice-president of ECOSOC to fill the unexpired term of ambassador Jean-Marc Hoscheit who had left the UN. On 15 January 2009 she was elected to a one year term as president of ECOSOC.
- "Presidents of ECOSOC", United Nations Economic and Social Council
- "Economic and Social Council Resumes 2008 Session to Fill Vacancies in Bureau, Subsidiary Bodies, While Wrapping up Other Outstanding Issues on Agenda" US Fed News (HT Syndication) 12 September 2008
- The Direction des Relations économiques internationales is also translated as "Directorate for International and Economic Relations", see "Biographies: Sylvie Lucas" "Special Event on Philanthropy and The Global Public Health Agenda" 23 February 2009, Trusteeship Council, ECOSOC, United Nations, New York
- "Curriculum vitae of H.E. Ms Sylvie Lucas", Luxembourg's United Nations office
- "Sylvie Lucas" Kobiety w polityce (Women in Politics), in Polish