The discussion emphasizes that all such systems make assumptions about the nature of law and legal reasoning. It describes and compares current projects in the field and analyzes the concepts that are central to expert systems in law. The text focuses on the jurisprudential problems of the structure of legal rules, the individuation of law, the relationship of logic to the law, and the nature of legal knowledge and reasoning. The discussion concludes that no theoretical obstacles exist to the development of rule-based systems of limited scope and uses examples from contemporary writings and from an analysis of a prototype expert system that operates in divorce law in Scotland. Footnotes, index, and 379 references.