On graduating from ESSEC, Christian Mulliez began his career in the Finance division of the pharmaceutical group Synthélabo in 1984. He was responsible for the group's Accounting and Finance operations from 1990 and went on to become Executive Vice-President, Administration & Finance in 1997. Following the merger with Sanofi, Christian Mulliez became Executive Vice-President Controller & Information Systems for the newly formed Sanofi-Synthélabo group. In 2000, he was appointed Executive Vice-President Finance. He joined L’Oréal in 2002 and took up his duties as Executive Vice-President Chief Financial Officer for the group in January, 2003.