Invited Contributions -- A Programming Model for Service Oriented Applications -- Software Engineering: Emerging Goals and Lasting Problems -- Distributed Systems -- GPSL: A Programming Language for Service Implementation -- A Formal Approach to Event-Based Architectures -- Engineering Self-protection for Autonomous Systems -- Orthogonal Process Activities -- A Graph-Based Approach to Transform XML Documents -- OMake: Designing a Scalable Build Process -- Automatic Generation of Tutorial Systems from Development Specification -- A Software Implementation Progress Model -- Behavioral Models and State Machines -- Regular Inference for State Machines with Parameters -- Automated Support for Building Behavioral Models of Event-Driven Systems -- A Behavioral Model for Software Containers -- Empirical Studies -- An Empirical Study of the Impact of Asynchronous Discussions on Remote Synchronous Requirements Meetings -- Evaluation of Expected Software Quality: A Customer's Viewpoint -- Using Design Metrics for Predicting System Flexibility -- Requirements and Design -- Combining Problem Frames and UML in the Description of Software Requirements -- Amplifying the Benefits of Design Patterns: From Specification Through Implementation -- The Good, the Bad and the Ugly: Well-Formedness of Live Sequence Charts -- Concerned About Separation -- Model-Based Development -- Algebraic Specification of a Model Transformation Engine -- Fundamentals of Debugging Using a Resolution Calculus -- A Technique to Represent and Generate Components in MDA/PIM for Automation -- Validation and Verification -- Argus: Online Statistical Bug Detection -- From Faults Via Test Purposes to Test Cases: On the Fault-Based Testing of Concurrent Systems -- Automated Systematic Testing of Open Distributed Programs -- Formal Simulation andAnalysis of the CASH Scheduling Algorithm in Real-Time Maude -- Tool Demonstrations -- JAG: JML Annotation Generation for Verifying Temporal Properties -- LearnLib: A Library for Automata Learning and Experimentation -- Software Evolution -- Trace-Based Memory Aliasing Across Program Versions -- The Pervasiveness of Global Data in Evolving Software Systems -- Relation of Code Clones and Change Couplings.

ETAPS 2006 was the ninth instance of the European Joint Conferences on Theory and Practice of Software. ETAPS is an annual federated conference that was established in 1998 by combining a number of existing and new conferences. This year it comprised ?ve conferences (CC, ESOP, FASE, FOSSACS, TACAS), 18 satellite workshops (AC- CAT, AVIS, CMCS, COCV, DCC, EAAI, FESCA, FRCSS, GT-VMT, LDTA, MBT, QAPL, SC, SLAP, SPIN, TERMGRAPH, WITS and WRLA), two tutorials, and seven invited lectures (not including those that were speci?c to the satellite events). We - ceived over 550 submissions to the ?ve conferences this year, giving an overall acc- tance rate of 23%, with acceptance rates below 30% for each conference. Congratu- tions to all the authors who made it to the ?nal programme! I hope that most of the other authorsstill founda way of participatingin this excitingevent and I hope you will continue submitting. The events that comprise ETAPS address various aspects of the system devel- ment process, including speci?cation, design, implementation, analysis and impro- ment. The languages, methodologies and tools which support these activities are all well within its scope. Di?erent blends of theory and practice are represented, with an inclination towards theory with a practical motivation on the one hand and soundly based practice on the other. Many of the issues involved in software design apply to systems in general, including hardware systems, and the emphasis on software is not intended to be exclusive.