Oppermann, ReinhardZiegler, Jürgen2017-06-222017-06-222005Summary This paper introduces context-adaptive information systems reflecting the current needs of the user. Context-adaptive information systems reflect more than classical user-adaptive systems where user and task characteristics are considered for adaptation. In context-adaptive information systems the usage episode is additionally defined by the time and the location, by the physical and social environment and the technical infrastructure and eventually by relevant situational characteristic such as sound, light or movement. To begin with, the rationality of adaptive systems and the concept of context-adaptiveness will be explained. Based upon the description of the three functions of adaptivity, i.e., the interaction logging, adaptation inference and adaptation performance, we describe user-adaptive and context-adaptive systems and the role sharing between the system and the user during the adaptation process. Techniques of location-awareness as currently an important determinant of context are descr...enContext-adaptivenessSituation-awarenessLocation-based information systemsAdaptivityAdaptabilityShared controlText/Journal Article1618-162X