The development of a methodology for using logic databases is essential if new users are to be able to use these systems effectively to solve their problems, and this remains a largely unrealized goal. A workshop was organized in conjunction with the ILPS '93 Conference in Vancouver in October 1993 to provide a forum for users and implementors of deductive systems to share their experience. The emphasis was on the use of deductive systems. In addition to paper presentations, a number of systems were demonstrated. The papers of this book were drawn largely from the papers presented at the workshop, which have been extended and revised for inclusion here, and also include some papers describing interesting applications that were not discussed at the workshop. The applications described here should be seen as a starting point: a number of promising application domains are identified, and several interesting application packages are described, which provide the inspiration for further development. Declarative rule-based database systems hold a lot of promise in a wide range of application domains, and we need a continued stream of application development to better understand this potential and how to use it effectively. This book contains the broadest collection to date of papers describing implemented, significant applications of logic databases, and database systems as well as potential database users in such areas as scientific data management and complex decision support.