In this paper we describe how we tried to solve a marketing information system need. First, we explain why we were gradually convinced it was necessary. The second step in our thinking was to list all the data we had and wanted to integrate in it. After that, obviously, we asked ourselves "what do we want to do with such a tool?" The following step was to try to find a package to meet our needs and, given the fact we found no one on the market, to try to develop one. This package has been developped by Sligos and Secodip and is now currently used in L'Oreal and Secodip since one year.