This work proposes an approach for managing multimedia information associated to 3D environments navigated by the user. The influence of context (location, user profile, user history, time, device and network) on such management is considered in different stages of the multimedia information lifecycle, with a particular reference to the authoring and presentation phases. The different types of contexts will be modeled (i.e., with a particular emphasis on location and user history) and analyzed in relation to content creation, leading both to the definition of a hierarchy of contexts and to a data structure modeled on authoring needs. Such formalizations will be then used as key components of an implementation architecture for controlling and proactively managing multimedia information in the presentation phase. Application examples related to cultural heritage are presented, showing how such architecture can manage complex user experiences on the basis of changes of context.