One of the central components of any such initiative is the conceptualization and implementation of information organization and representation strategies and tools to facilitate information access and interaction. Solid and well established cultural heritage digital libraries address information organization and representation in their business, strategic and sustainability plans for effective and efficient information access and retrieval. The variety of digital objects, digital formats and digital artefacts found in cultural heritage collections make this task a challenging undertaking that requires proper planning, including not only indexing and tagging of materials but also the ways in which indexes and tags can be effectively incorporated into the information architecture and search functionalities of the underlying systems and architectures. Knowledge organization systems (KOS) have been widely used in digital libraries, subject repositories and open archives. The term "knowledge organization