This article presents the conceptual communication model of dynamic groups, that dynamically utilizes three traditional communication metaphors through the use of context-based information. Dynamic groups makes creation, management and usage of groups easy. It enables social network structures to be maintained in both virtual and face-to-face settings as well as in the combination thereof. This article defines the dynamic management of advanced contact lists which can include presence and status information, a/synchronous multimedia communication tools, and methods for structuring social networks. It also contains an initial evaluation and a proposed architecture for technical realisation.