This paper was read at the Planning Conference for the projected Artists’ Papers Index, held at the British Library in September 1985. Dr. Brown discusses some problems inherent in the definition of such an index or register of artists’ papers. The author, who is responsible for manuscripts and archives relating to artists and art history in the National Library of Scotland, goes on to outline the resources for art-historical study to be found in one large general manuscript collection-a major collection that is part of an institution with a long-established and very active acquisitions policy in this field.