The aim of this paper is to compare matrix- and list-based configuration rule visualization methods in order to find the effects of using a certain visualization method. Especially, the visualizations’ impact on readability and how the configuration rules are authored are studied. A case study was conducted at two automotive manufacturing companies. The research method included to observe users as they were authoring configuration rules, to study the visualization methods, and to interviews users of the PDM system visualizing the configuration rules. It was found that common aim for the users is to author easy to read configuration rules, which this paper shows is highly dependent on the visualization method. The conclusion is thereby that the choice of visualization method influence how the configuration rules are authored.