English summary: It is not always easy to decide whether an object of art or an antiquity is authentic or not. On the one hand, there is a gradual transition from "improving" restoration to outright deceit. On the other hand, the methods applied in the production of fakes become ever more sophisticated so that fakes are sometimes incorporated even in respected and well-known collections. This situation is even more unfortunate as these collections represent points of reference for further stylistic investigations and comparisons. Bochum-based foundation Situation Kunst owns a substantial collection of West African art which has been the subject of controversial opinions concerning its authenticity. The questions posed in the title of this book gave rise to an exchange of positions and experiences between art historians, ethnologists, scientists and restorers at a meeting at Ruhr-University Bochum in February 2007. The results of this memorable symposium are collected in this volume.