The standardization of the IMS as a multi-access network implies that it can be accessed by different classes of terminals. Even at the heart of the same class of terminals (mobile phones for example), we are witnessing an increasingly divergent range of hardware and software capabilities (screen size, memory, OS). As a result of this heterogeneity, users may receive content that is not compatible with their device capabilities, and may even be unable to display this content. In order to ensure a better service and an optimal user experience, terminals should be able to communicate their capabilities to the network. The network could then use these capabilities to adapt its services and it may communicate them to other users as well. In this paper, we establish a state of the art concerning existing methods for indicating terminal capabilities in IMS. This state of the art will be used to design the architecture and the necessary mechanisms to implement this service in IMS, while takin...