The notion of Federated Data Warehouse Architecture was suggested for various reasons: bigger autonomy of divisions in an organization, better adaptation to user needs, bigger efficiency of treatment. However this architecture puts the problem of cooperation between its constituents. Because of the heterogeneities which can exist, the simultaneous use of constituents can be made difficult. In this paper we propose a process to build an integrated vision. This integrated vision permits the simultaneous exploitation of the constituents. It is based on a generic model to describe the structure of data warehouses. A relational implementation is suggested.