The BBC Archive is one of the world’s largest multimedia archives, held in 27 locations across the UK. The Archive contains over 2 million items of TV and video, 300,000 hours of audio, 6 million still photographs, over 4 million items of sheet music, and over half-a-million documents and records. It is a working media library, fulfilling some 4,000 loans per week, as well as preserving content as part of the UK’s national cultural heritage. A team of cataloguers and media managers classify a selection of current content, as well as enhancing cataloguing and classification of legacy content. There are two major classification schemes used in the Archive, both numerical, and one based on UDC. Lonclass, based on UDC, was developed first, then Telclass, which is used by the Natural History Unit in Bristol. In addition, there are many and various controlled vocabularies that have been developed to tag content in the different nations (Scotland, Wales, and Northern Ireland) and the English regions.