In contrast to registration, cataloguing is a complex task, whose intended beneficiaries are both the staff of the archive and the outside users of the archive's·collection. The purpose of a catalogue is to provide, in systematic form, information on the items contained in a collection in sufficient detail to enable those who have to administer that collection or who wish to use those items to do so as efficiently as possible. Efficiency, in this context, means both the minimum waste of time and the minimum unnecessary usage of the recordings in the archive.

Information normally held in the catalogue falls into several categories, although their precise nature will obviously vary with the type of material catalogued, as is shown in the case studies at the end of this chapter. In many archives, the information categorised here is not all held in a single physical catalogue - a system of parallel files may be a perfectly acceptable alternative. It remains, however, a part of 'catalogue' information.

The first category is the formal identification of the recording catalogued: formal identification is identification made accurately within the rules and practices established by the archive, as distinct from the simple identification made at registration. What constitutes correct identification will vary with the material collected: an archive of commercial recordings will use the title that appears on the item catalogued, where an archive of wildlife recordings will use the correct scientific designation of the species recorded and an oral history collection the name of the person interviewed.

Since the formal primary identification of the recording may not actually be very informative, a major part of catalogue information consists of the elaboration of that identification. For collections of commercial recordings, this will generally approximate to the procedures traditional to the cataloguing of published material -the linking of title to statements of responsibility (i.e. the identification of composers or authors, performers, etc.). Collections of non-commercial recordings will have different priorities, depending on the nature of the material collected. Ethnomusicology recordings, for example, which may be identified in the first instance by the name of their collector, will require as additional information geographic (or linguistic or anthropological, or a combination of these) indications of the circumstances of the recording, including a date, and information on what was recorded. An archive collecting the proceedings of a national legislature would require information identifying the session (day and time), the topic and the speakers in a debate or committee, with, perhaps, reference to the published (transcribed) proceedings.

The purpose of providing this level of information is, first, to make unambiguous the identification of the recording (to establish, in other words, that an item is not merely a recording of Stravinsky's 'The Rite of Spring' but is the recording made by a particular orchestra and conductor on a specified occasion) and, second, to provide sufficient detail to enable an interested potential user to assess whether or not a recording contains material appropriate to his or her interests. Thus in the field of material culture a catalogue entry should make clear exactly which processes are being explained and from what perspective; in oral history, the catalogue links an interview to topics, and shows how the person interviewed relates to them. Reading the catalogue cannot be a substitute for using the collection, but a catalogue should ensure that the collection is not wastefully used and that the user's interests are matched to the material listened to as precisely as possible. This will commonly mean that users are guided not merely to specific recordings, but to specific sections of recordings. Lengthy items (especially those generated by field workers) are divided into sections -reels, timed passages, audibly-signalled segments -and the divisions reflected in the catalogue summary or synopsis.

Further categories of catalogue information include technical data on the recording, indicating the form in which it was first recorded and the form in which it would be made available to users. An archive covering more than one language will need to specify the language of recordings. The circumstances of the production of the recording would be included as subsidiary information when they do not form part of the full or elaborated identification; details of acquisition are similarly covered. This information overlaps into the question of copyright and other restrictions on access to, or use of, the material. Finally, an archive will wish to establish connections between the recording catalogued and related material such as further recordings, transcripts, related documents (photographs or text connected with the item catalogued) and bibliographic citations.

It will readily be seen that a catalogue entry providing all of the information suggested in this section will be a lengthy document in its own right. It will also be appreciated that by no means all of these details need (or indeed should) be available to all readers of the catalogue. This is best exemplified in the area of technical information. For the purposes of its own technical staff, and perhaps for professional or commercial users, an archive will need extensive details on the recording, including perhaps the machinery, tape and configuration used in the original recording. For a casual user, however, the knowledge that all recordings are made available on stereo cassette 'listening copies' might make the entire category of technical information redundant in a version of the catalogue provided for general access or sale. To take another example, the question of restriction may involve information confidential to the archive and the person concerned with the recording, when all a user need know is that there are (or are not) restrictions. These considerations underline the statement made earlier, that the product of the cataloguing process need not be a single catalogue. The provision of separate 'internal' and 'external' catalogues, or the supplementing of an open catalogue with restricted files of detailed technical or confidential information, would be acceptable, indeed logical, procedures. The essential qualification, of course, is that cross-reference between all sources of information be quick and precise. This is guaranteed by the use of a single unambiguous label to identify the recording wherever it is mentioned; the accession number is the obvious choice for such a label.