AACR2 Second Edition

AACR2 stands for the Anglo-American Cataloguing Rules, Second Edition. It is published jointly by the American Library Association, the Canadian Library Association, and the Chartered Institute of Library and Information Professionals. AACR2 is designed for use in the construction of catalogues and other lists in general libraries of all sizes. The rules cover the description of, and the provision of access points for, all library materials commonly collected at the present time.
Despite the claim to be 'Anglo-American', the first edition of AACR was published in 1967 in somewhat distinct North American and British texts. The second edition of 1978 unified the two sets of rules (adopting the British spelling 'cataloguing') and brought them in line with the International Standard Bibliographic Description. Libraries wishing to migrate from the previous North American text were obliged to implement 'desuperimposition', a substantial change in the form of headings for corporate bodies.
Principles of AACR include cataloguing from the item 'in hand' rather than inferring information from external sources and the concept of the 'chief source of information' which is preferred where conflicts exist.
As well as occasional minor amendments, a broader revision is under way with a view to a new edition in which the rules are more consistent and coherent, informed by the Functional Requirements for Bibliographic Records. This 'AACR3' has the working title 'Resource Description and Access'.
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