Analyzing Complex Systems: Only a Complex of Techniques Can Do the Job

Analyzing a complex system means analyzing the world in which the system functions, or the "context of use". If we want to design systems for the context of use, we need to take the task world into consideration. Based on a framework derived from Jordan we will elaborate the "map" of sources of knowledge of the task and context of use of interactive systems. We provide an overview of the relevant techniques, the validity issues related to them and their pitfalls, as well as the problem of combining insight gained from applying different techniques into a unified view or task model.