In rich pervasive environments, there will be numerous opportunities for end users to dynamically create services of interest by causing two or more devices or resources to interoperate together, often under changing circumstances. In general, users find this kind of process hard to manage. Existing programming architectures make the situation difficult to address in a principled, scaleable way. Users find it hard to tackle such problems via devices with small, resource-poor user interfaces. It is proposed that a good theoretical basis for addressing an essential aspect of all of these problems is the theory of Direct Combination. When the Direct Combination framework, based on the theory, is applied to spontaneous interactions, the user interface can be made relatively simple, and the amount of search required by the user to specify desired actions can be greatly reduced. We present Direct Combination (DC) and the new interaction techniques it gives rise to for pervasive environments. We consider two different support architectures. We argue that one of these, the role-based architecture, has particularly good properties for modelling rapidly changing pervasive environments, and for highly distributed implementations. We demonstrate how the concept of viewpoints can be used to focus, filter and afford operations, and how this can be well supported by the role-based architecture
