An aspect-oriented specification technique that supports the specification of component-based distributed systems is presented. Importantly, this technique also supports the synthesis of quality of service management components from particular aspects of the specification. It is described how, by using a tool to support the aspect-oriented environment, one can first specify and verify QoS management subsystems and then synthesise components that can be placed into a running system. The focus is on dynamic QoS management functions, particularly monitoring and adaptation. The approach is illustrated by giving a simple example of the dynamic QoS management of an audio stream.