Knowledge-based configuration (of complex products and services) has a long history as an artificial intelligence application area, see, e.g.[B 1][A 1][A 6][A 7][A 8][A 9][A 10][A 11] Informally, configuration can be defined as a "special case of design activity, where the artifact being configured is assembled from instances of a fixed set of well-defined component types which can be composed conforming to a set of constraints".[A 2] Such constraints[B 4] are representing technical restrictions, restrictions related to economic aspects, and conditions related to production processes. The result of a configuration process is a product configuration (concrete configuration), i.e., a list of instances and in some cases also connections between these instances. Examples of such configurations are computers to be delivered or financial service portfolio offers (e.g., a combination of loan and corresponding risk insurance).