Modern databases and information systems essentially differ from their predecessors. Ontology-based and knowledge-based approaches to system development, UML based IS development methodologies, XML databases and heterogeneous information models have come to the fore. All these fundamental aspects are discussed in this book. This publication contains a collection of 22 high quality papers written by 44 authors. These articles present original results in modern database technologies, database applications, data warehousing, data mining, ontologies, and modern information systems. Special emphasis is put on multimedia database systems, heterogeneous data integration methods, view optimizations, ontology engineering tools, modeling and model transformations (MDA). Theoretical aspects as well as technical development issues are considered. The intended audience for this book is researchers, advanced students and practitioners who are interested in advanced topics on databases and information systems.