The purpose of this account is to set out the results of 3 years of concrete experience gained on this model and its simulation software. It breaks down into three main sections: I. The principle of the model insofar as concerns data collection and the econometric assessment of the latter. II. The various types of simulation which are possible with the software; various examples are given in this connection. III. The setting up a new mode of cooperation between the advertiser's marketing departments and the company making the studies.