Digital products constitute a growing class of economic goods that are increasingly traded via digital networks. In distributed digital networks, it is required that digital products adapt to heterogeneous requirements of electronic markets and subsequent usage environments. Adaptation depends on various kinds of information types that characterise a digital product. In this article we will present a self-describing container model for digital products, called KCO, that integrates characteristic semantic information types (facets) derived from an analysis of electronic market structures. Semantic information supports usage of digital products throughout the whole product life-cycle. During purchase decision phases, facets offer semantically annotated data on the quality and applicability of a digital product while in usage contexts, facets provide data that can be used by content management systems for content processing tasks, such as access control, routing, syndication and aggregration. KCOs allow exchanges between existing heterogeneous application environments on the basis of an open Knowledge Content Transfer Protocol (KCTP) that is part of a general architecture (Knowledge Content Carrier Architecture, KCCA). All architectural elements have been used in three application environments.1