These two trends-the massive increase in computational power and the expanding context in which we put that power to use-both suggest that we need new ways of interacting with computers, ways that are bet­ter tuned to our needs and abilities. Over the last few years, research into Human-Computer Interaction (HCI) has begun to explore ways to con­trol and interact with a new breed of computer systems. Prototype sys­tems have been developed; new forms of interaction explored; new research groups established; new designs developed and tested.