After earning degrees in business (Ecole des Hautes Etudes Commerciales 1978) and in law (Université de Paris 1979), Bertrand de Mazières joined the French Treasury on graduating from l’Ecole Nationale d’Administration in 1982. He was Financial Attaché at the French Embassy in Washington from 1986 to 1988, Head of the banking division at the Treasury from 1989 to 1993 and Deputy Secretary for debt and development from 1993 to 1996. In this latter capacity he was Vice-President of the Paris Club in charge of negotiating the restructuring of sovereign debt from 1993 to 1996.
Bertrand de Mazières was nominated General Secretary and Chief of staff of the Conseil des Marchés Financiers CMF in October 1996, when the CMF was founded as the regulatory agency responsible for the good conduct and the professional standards of the French investment services providers, for the supervision of both regulated and off-market operations in France, and for the authorisation of tender offers. He held this office until CMF and another regulatory agency, the Commission des Opérations de Bourse COB, were merged into the Autorité des Marchés Financiers AMF in November 2003.
In December 2003, he was appointed Chief Executive of Agence France Trésor, the division of the Ministry of Economy and Finance responsible for the management of the debt and treasury of the French Republic. He held this post until August 2006 when he left to join the European Investment Bank as its Director General for Finance. In June 2007, he was also elected President of AMTE (Euro Debt Market Association).