Software architecture has emerged as an important subdiscipline of software engineering encompassing a broad set of languages, styles, models, tools, and processes. The role of software architecture in the engineering of software-intensive applications has become more and more important and widespread. Indeed, component-based and service-oriented architectures have become key to the design, development, and evolution of most software systems. The European Conference on Software Architecture (ECSA) is the premier European conference dedicated to the field of software architecture, covering all architectural features of software and service engineering. It is the follow-up of a successful series of European workshops on software architecture held in the United Kingdom in 2004 (Springer LNCS 3047), Italy in 2005 (Springer LNCS 3527), and France in 2006 (Springer LNCS 4344). Due to its success, it has evolved into a fu- fledged series of European conferences whose first edition was ECSA 2007, held in Madrid, Spain September 24–26, 2007. ECSA 2007 provided an international forum for researchers and practitioners from academia and industry to present innovative research and to discuss a wide range of topics in the area of software architecture. It focused on formalisms, technologies, and processes for describing, verifying, validating, transforming, building, and evolving software systems, in particular founded on component-based and service-oriented architectures. Covered topics included architecture modeling, architectural aspects, architecture analysis, transformation and synthesis, quality attributes, model-driven engineering, and architecture-based support for developing, adapting, reconfiguring, and evolving component-based and service-oriented systems.