Integrated resource management for small, hand-held mobile computers is addressed. The apporach is based on the concept of quality of service (QoS). The focus is on provinding for detection and adaption, not on transparency. The large and rapid changes in the services and resources available to mobile computers cannot be made transparent, neither to the user nor to system or application software. On the contrary, detection of changes and adaptation to new service and resource levels is necessary in all software layers in order to maximise the potential of the machine.