Service-based systems engineering has proven useful in the development of telecommunication systems, helping to modularize complex system functionality with high degree of interaction between system components.
Increasingly, the notion of service is gaining ground in other application domains like spontaneous networks, ubiquitous computing, and safety-critical systems from the automotive or avionics domain.

Precise specification and correct implementation of requirements for services are essential in most of these application domains. Jini, .NET, and SOAP are examples of recently proposed middleware technologies in which syntactic service notions play an important role as an implementation concept.
Surprisingly, however, no precise mathematical foundation supporting the use of services across development phases exists to date. Many notions of service, like those used in the middleware technologies mentioned above, refer only to syntactic interfaces. This is inadequate for more elaborate service specifications that include, for instance, Quality-of-Service properties. Consequently, services are not treated as first-class modeling elements, say, in UML/UML-RT and SDL.

Therefore, especially in the application domains mentioned above, a suitable notion of service is needed to support service-based software engineering beyond simplistic syntactic approaches.

A solid methodological basis for service-oriented system development requires a suitable notion of service and the availability of systematic modeling, development, and quality assurance methods based on this service notion. Therefore, the topics addressed in this workshop include:

• Formal foundations for services
• Modeling notations for services
• Composition operators for services
• Quality-of-Service specifications
• Patterns for service development
• Methodologies for service-oriented system engineering
• Refinement and refactoring techniques for services
• Service-oriented validation and verification techniques