Workshop Reports.- Reflection and Meta-level Architectures: State of the Art and Future Trends.- Exception Handling in Object Oriented Systems.- Object-Orientation and Operating Systems.- Formal Techniques for Java Programs.- Component-Oriented Programming.- Tools and Environments for Understanding Object-Oriented Concepts.- PhDOOS 2000: The 10th Ph.D. Workshop on Object-Oriented Systems.- Quantitative Approaches in Object-Oriented Software Engineering.- Metadata and Adaptive Object-Models.- Defining Precise Semantics for UML.- Objects and Classification.- Object-Oriented Architectural Evolution.- Specification, Implementation, and Validation of Object-Oriented Embedded Systems.- Quality of Service in Distributed Object Systems.- XML and Object Technology.- Workshop on Aspects and Dimensions of Concern: Requirements on, and Challenge Problems for, Advanced Separation of Concerns.- Mobile Object Systems.- New Issues in Object Interoperability.- Panel Report.- Panel Session: Mobile Code, Internet Security, and E-Commerce.- Posters.- Poster Session.