 The use of open ontologies and standards to structure, represent and convey those descriptions as well as to specify the kind of adaptation operations is vital for the success of UMA.This is especially true in loosely coupled environments such as the Internet, where heterogeneous end-users devices, varied content formats, repositories and networking technologies co-exist.Standards from the W3C such as OWL (Web Ontology Language) or CC/PP (Content Capability/Preferences Profile) and from ISO/IEC such as MPEG-7 and especially MPEG-21, are well-suited for the implementation of UMA-enabler systems.