Résumé en anglais

The article shows a surprising way of how management consultant's daily practices play a role in managers' decisions. Beyond the traditionally recognized roles of consultants (high level staff, energy catalyst), we pinpoint the importance of information transmission and the ambiguity of this latter.In fact, our field studies show that management consultants realize daily marginal transgressions of confidentiality rules. They favour the transmission to competitors of useful information which is not supposed to be transmitted but does not threaten firm's existence. In doing so, management consultants actually act as sensitive information hawkers who fertilize firm's decision making.