The concept of vitality has been at the heart of research related to the development of OLMCs for over 40 years. However, as Raymond Théberge, the Commissioner of Official Languages, mentioned, the heritage dimension has not been fully considered, despite the importance of a community’s place in time. The concept of vitality of memory (Roy, 2021) is intended to respond to this, but it is still necessary to understand why this issue has been absent from the discussions to date. We therefore propose first to review the genesis of the concept, and then to provide an overview of the various dimensions addressed, whether ethnolinguistic, institutional, territorial or artistic. In the second part, we propose to expand the concept of vitality by integrating the temporal dimension. After a review of the global approach adopted, we present the main characteristics of the concept of vitality of memory, a contribution to a multidisciplinary approach to memorial phenomena.