Service-oriented Architectures are tailored and used for business applications across several enterprises. Services provide access to business data and allow managing business workflows. They flexibly integrate functionality across platforms and providers by using web service technology. However, these services are not directly used by end users. User interfaces together with complex control logic must be developed as an additional layer on top of services. This development step is insufficiently supported by existing methodologies and tools. Instead, user interfaces are designed manually for service interfaces and business processes.