Introduction

Formalization of the notion of cost seems to be linked to the advent of mass production, which makes use of shared resources. The notion of cost gave way to that of a costing method meant for the dissemination of a practice. More recently, we have moved from the notion of method to that of costing systems. Here it is not a question of defining a method of calculating, but of organizing data in view of the multiple analyses in the domain of costs and in the relational domain of analysis of profitability. The spectacular progression of computer science, both in terms of capacity of processing and in potential of modelling, makes the task of the designer of costing systems at once easier and more complex. Everything, or almost everything, is possible in the domain of collection and processing of data, but the output still has to be intel­ligible, flexible for users and unambiguous. One may dream of a vast warehouse of data where everyone, as needs dictate, finds the requisite data. But to obtain a minimum of coherence in such a world, users would have to share the same model of organization and its environ­ment, and a like capacity for handling techno-economic data which is the raw material of all calculations of cost.