The purpose of this catalogue is to promote interaction between members of the AI community. It will do this by announcing the existence of AI techniques and portable software, and acting as 30 pointer into the literature. Thus the AI community will have access to 30 common, extensional definition of the field, which will: promote 30 common terminology, discourage the reinvention of w heels, and act as 30 clearing house for ideas and software. The catalogue is 30 reference work providing 30 quick guide to the AI tools ava.ilable for different jobs. It is not intended to be 30 textbook like the Artificial Intelligence Handbook. It, intentiona11y, only provides 30 brief description of each tool, with no extended discussion of the historical origin of the tool or how it has been used in particular AI programs. The focus is on techniques abstracted from their historical origins. The original version of the catalogue, was hastily built in 1983 as part of the UK SERC-DoI, IKBS, Architecture Study. It has now been adopted by the UK Alvey Programme and is both kept as an on-line document undergoing constant revision and refinement and published as 30 paperback by Springer-Verlag. Springer-Verlag have agreed to reprint the Catalogue at frequent intervals in order to keep it up to date.