Graduate of Rouen business school, auditor and chartered accountant, Philippe Castagnac started his career at Mazars in 1978. 
He became a partner in 1988 and has extensive experience in auditing and advising a large number of listed companies in the service and industrial sectors, in France and the United States. He has been a member of Mazars’ Executive Committee and Deputy C.E.O. of Mazars since 1st January 2004.  In December 2006 he was elected to the Group Executive Board and the Executive Committee as C.E.O. of Mazars in France.  Philippe Castagnac was also a member of the CRCC of Paris (Compagnie Régionale des Commissaires aux Comptes) and a representative of the Paris Company at the CNCC (French National Audit Institute).
He was also chairman of the Alsace CRCC (Compagnie Régionale des Commissaires aux Comptes) from 1994 to 1999, and presided the Commission on the “LSF decree” within the CNCC in 2002 and 2003.