Encarnação, José L.Oberquelle, HorstOppermann, ReinhardKrause, Jürgen2017-11-222017-11-2220013-519-02748-8https://dl.gi.de/handle/20.500.12116/6922A human being’s daily activities – professional or private – are based on a broad range of interactions with numerous external objects: discussing project plans with colleagues, setting up a multimedia presentation in the conference room, editing documents, delegating travel planning to a secretary, driving a car, buying a ticket from a vending machine, visiting an exhibition, controlling the TV at home, etc. As computers are becoming more and more ubiquitous, moving from the desktop into the infrastructure of our everyday life, they begin to influence the way we interact with this environment – the (physical) entities that we operate upon in order to achieve our daily goals. The most important aspect of future human-computer interaction therefore is the way, computers support us in efficiently managing our personal environment. This might be called the ecological level of user-interface design.enText/Conference Paper