Pervasive Computing leads to dramatic changes in information technology in general: As a consequence of enormous progress in processor speed and storage capacity and - at the same time - extreme reduction in size and power consumption computers will be more and more invisible. They can be embedded into clothes or into tools of our daily life. Progress in wireless communication technology leads to a “network of everything“ [Mat01] and to an information exchange between these. Closely related to these technologies are new developments in the database and information systems area.. Information will be ubiquitous: Relevant information must be made available to anybody anytime and everywhere, depending on the context.