The National Museum consists of five specialised institutes - the Museum of Natural Sciences, the Historical Museum, the Library of the National Museum, the Náprstek Museum of Asian, African and American Cultures (part of the National Museum since 1932), the Czech Museum of Music (part of the National Museum since 1984) and two technical and administrative departments – the Department of Economic Management and the Department of Central Exhibiting and Collecting Work. The National Museum accumulates collections of material documents of natural history, prehistory and history of Czech and foreign provenance, especially in the field of mineralogy, geology, petrology, paleontology, hydrobiology, micology, botanics, entomology, zoology, antropology, prehistory and protohistory, medieval archeology, classical archeology, Czech history, ethnography, numismatics (including non-European), history of theatre, history of physical education and sport, prehistory and ancient history of the Near East and Africa, non-European ethnography, Asian culture, musicology and bibliology. Collections are created in line with scientific research and according to the museum’s own conception of collecting work. The museum is in charge of the historical book fund, castle libraries, a specialised public library and a specialised archive.