This document provides an overview of RDA (Resource Description and Access) and how it improves upon AACR2 (Anglo-American Cataloguing Rules, 2nd edition). It notes that RDA was developed starting in 1978 to create a single international cataloging standard. RDA addresses weaknesses in AACR2 like inconsistent language, lack of support for cataloger judgment, and inability to describe 21st century materials. RDA is better suited for the future of cataloging and will replace AACR2 in 2010.