It holds and preserves the largest multimedia collection in existence of the materials of Irish traditional music. In addition to thousands of sound recordings, it hosts books and serials, photographs, sheet music, DVDs, posters, catalogues and more. It also holds the largest body in existence of information about Irish traditional music, contemporary and historic, organised on customised computer databases, indexes and stock-lists. Founded with the Breandán Breathnach Collection, the collection has been expanded through donations by radio, television, libraries and private collectors, among other means.