This volume constitutes the proceedings of REFLECTION 2001, the Third Int- national Conference on Metalevel Architectures and Separation of Crosscutting Concerns, which was held in Kyoto, September 25-28, 2001.

Reflection and SOC in Java.- JAC: A Flexible Solution for Aspect-Oriented Programming in Java.- Reflex — Towards an Open Reflective Extension of Java.- System Checkpointing Using Reflection and Program Analysis.- Software Adaptation Using Reflectionn and SOC Techniques.- Experiments with JavaPod, a Platform Designed for the Adaptation of Non-functional Properties.- DJ: Dynamic Adaptive Programming in Java.- The K-Component Architecture Meta-Model for Self-Adaptive Software.- Reflective Middleware for Distributed Mobile Applications.- Separation of Concerns in Mobile Agent Applications.- Dynamic Adaptability: The MoléNE Experiment.- A simple security–Aware MOP for Java.- Reflective Middleware Solutions for Context-Aware Applications.- Testing and Verification of Reflective and SOC Systems.- Testing MetaObject Protocols Generated by Open Compilers for Safety-Critical Systems.- Supporting Formal Verification of Crosscutting Concerns.- Foundations of Reflection and Separations of Concerns.- A formal definition of crosscuts.- Process-Algebraic Foundations of Aspect-Oriented Programming.- UML Reflections.- Software Methodologies for Separation of Concerns.- A Hybrid Approach to Separation of Concerns: The Story of SADES.- Coping with Crosscutting Software Changes Using Information Transparency.- Poster Session.- Template Metaprogramming an Object Interface to Relational Tables.- Performance and Integrity in the OpenORB Reflective Middleware.- Data Abstraction in AspectJ.- Towards Coping with Role-Binding Anomaly.- Removing Reflection from Java Programs Using Partial Evaluation.- Open Implementation of UML Meta-model(s) Making Meta-modeling and Meta-programming Meet.- JavaCloak: Reflecting on Java Typing for Class Reuse Using Proxies.- Aspects of Exceptions at theMeta-level.