Anglo-American Cataloguing Rules

The rules cover the physical description of library resources, as well as the provision of name and title access points.

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 (ISBD).

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.

While the 2002 updates included substantial improvements to AACR's treatment of non-book materials, the proliferation of 21st century formats in a networked environment and the rise of electronic publishing signaled the necessity for significant change in the cataloging code.

Informed by the work of the International Federation of Library Associations and Institutions (IFLA) Functional Requirements for Bibliographic Records (FRBR), the new framework was crafted to be more flexible and suitable for use in a digital environment: Resource Description and Access (RDA) was released in June 2010.