The activity-based management or the activity-based accounting – several names for a new technique that seems to impose itself in the field of cost and performance management. Some think of it as just another means of cost allocation, others as a way of fighting against dissipation. Several mutations induced by the ABC method are: the uselessness of identifying principal and auxiliary cost pools or manufacturing and support activities; the transformation of fixed costs into variable ones; the redefinition of the cost of underutilization of production facilities; the increased number of cost objects. Our aim is to analyze and discuss these evolutions.