Knowledge capitalization is becoming a strategy game for companies. A possible approach for Knowledge Management inside an organization could be the construction of an organizational memory. The Information and Communication Technologies (ICT) are offering the infrastructure and the tools in order to materialize this memory in a diversity of forms:  a database, a documentary base, a knowledge base, a case base or a groupware tool. This paper (1) presents the various aspects of the concept of organizational memory (2) makes a typological analysis of memory (3) describes the forms of representation and the development tools.