Article dans une revue: A statistical analysis of the impact of the decisions rendered by the Conseil de la concurrence between 1992 and 2000 shows that competition policy was having a far greater impact than the direct harm caused by the imposition of fines, which were small in that period. On average, an event such as an interrogation of firm representatives by the DGCCRF, a decision by the Minister of Finance to ask the Conseil de la concurrence to investigate a case, or a Decision imposing pecuniary and non-pecuniary sanctions, caused the share price of affected firms to fall significantly. These results suggest that competition policy succeeded in changing firms' behaviour in an important way.