Deductive databases and object-oriented databases are at the forefront of research in next-generation intelligent database systems.Object-oriented programming and design methodologies have great potential, promising to reduce the complexity of very large software systems in such domains as computer-aided design and manufacturing, integrated office information systems, and artificial intelligence. Object-oriented database systems will enhance the programmer/user productivity of such systems. Research into deductive databases is aimed at discovering efficient schemes to uniformly represent assertions and deductive rules, and to respond to highly expressive queries against the knowledge base of assertions and rules. This area of research is strongly interacting with Logic Programming which has developed in parallel, sharing Logic as a common basis. Recently, research has aimed at integrating the object-oriented paradigm and rule-based deduction to provide a single powerful framework for intelligent database systems.The aim of this book is to present research papers and technical discussions between researchers concerned with deductive databases, object-oriented databases, and their integration.