The cartel leniency programs developed in the U.S. and in other jurisdictions around the world have been considered remarkably successful. A critical look at leniency programs, however, should give some pause, especially as leniency programs proliferate around the globe. First, the powerful incentives created by these programs sometimes encourage companies to rush unduly to seek leniency even when the conduct at issue is at worse ambiguous. Second, during some investigations, companies and their counsel “stretch” the facts in order to secure the prized leniency. Finally, when penalties in these cases are imposed, often rigid fining guidelines make it difficult for the authorities to impose fines appropriate to the gravity of the offense. As the number of leniency programs grows, it is important for enforcement authorities to consider corrective steps before these problems undermine the success of the leniency concept