Direct Combination (DC) is a recently introduced user interaction principle. The principle (previously applied to desktop
computing) can greatly reduce the degree of search, time, and attention required to operate user interfaces. We argue that
Direct Combination applies particularly aptly to mobile computing devices, given appropriate interaction techniques, examples
of which are presented here. The reduction in search afforded to users can be applied to address several issues in mobile
and ubiquitous user interaction including: limited feedback bandwidth; minimal attention situations; and the need for ad-hoc
spontaneous interoperation and dynamic reconfiguration of multiple devices. When Direct Combination is extended and adapted
to fit the demands of mobile and ubiquitous HCI, we refer to it as Ambient Combination (AC). Direct Combination allows the user to exploit objects in the environment to narrow down the range of interactions that need
be considered (by system and user). When the DC technique of pairwise or n-fold combination is applicable, it can greatly
lessen the demands on users for memorisation and interface navigation. Direct Combination also appears to offers a new way
of applying context-aware information. In this paper, we present Direct Combination as applied ambiently through a series
of interaction scenarios, using an implemented prototype system.