Cataloguing is an important activity in a library. It forms the basis for information retrieval. Facilitating effective retrieval of information is the primary objective of any information system / library. Over the years, we witness that the number of rules in AACR have increased like other codes in tune with the emergence of various types of documents. Obviously, it became very difficult for the cataloguer to remember all these rules in order to effectively catalogue a document. The book explains a step by step approach in building an expert system for Part 1 (rules for bibliographic description) of AACR2.