This book constitutes the strictly refereed post-workshop proceedings of the Third International Workshop on Rules in Database Systems, RIDS '97, held in Sk?vde, June 1997. The 13 revised papers presented in the book were carefully reviewed and selected from 33 submissions. The book documents the state-of-the art in the area. The papers are devoted to deductive databases, active database systems architectures, events in workflow management, rule modelling and simulation, rule confluence, rule termination analysis, rule testing and validation, active database systems design.