AACR2R

AACR2R stands for the Anglo-American Cataloguing Rules, Second Edition, Revised. It is a revision of AACR2 that updated descriptive cataloging guidelines to address evolving library practices, including new media formats and the increasing role of electronic resources. Developed by major library standards bodies, AACR2R aimed to provide clearer guidance for creating bibliographic records and establishing consistent access points across languages and formats.

The rules cover the core elements of description and access, including how to record authorship, titles, edition statements, publication information, physical description, series data, and notes. They also address the construction of access points such as main entry and added entries, capitalization and punctuation, and the use of uniform titles. The approach sought to harmonize cataloging practices across different resource types (print, electronic, audiovisual, and digital resources) and to improve searching and retrieval in library catalogs.

In practice, AACR2R was widely adopted in libraries and aligned with MARC bibliographic formats, providing a cohesive framework for description and indexing during a period of rapid technological change. It facilitated more consistent catalog records in the transition from traditional print resources to digital and remote access.

With the development of new conceptual models and metadata practices, many libraries began transitioning to RDA (Resource Description and Access) in the 2010s, which was designed to better accommodate FRBR/FRAD concepts and web-based resources. As a result, AACR2R has been largely superseded, though some institutions incorporated its guidelines into local practices or maintained legacy records under AACR2R.