: Multimedia streaming means delivering continuous data to a plethora of client devices. Besides the actual data transport, this also needs a high degree of content adaptation respecting the end users’ needs given by content preferences, transcoding constraints, and device capabilities. Such adaptations can be performed in many ways, usually on the media server. However, when it comes to content editing, like mixing in subtitles or picture-in-picture composition, relying on third party service providers may be necessary. For economic reasons this should be done in a service-oriented way, because a lot of adaptation modules can be reused within different adaptation workflows. Although service-oriented architectures have become widely accepted in the Web community, the multimedia environment is still dominated by monolithic systems. The main reason is the insufficient support for working with continuous data: generally the suitability of Web services for handling complex data types and...