Up to now product configurators have been referred to as software to simplify the configuration process for complex products with various features (including services). Configurators particularly include consistency checks in order to permit only valid configurations. Invalid configurations result, for example, from technical reasons as complex products regularly have mutually exclusive features (Lackes and Schnoedt 1999, p 212). Primary users are, for example, salespersons in the businessto-business context that need assistance with complex products. Another application is in the business-to-consumer sector where customers configure a product using their home computer. In some cases a configurator is the constituent component of an order process.