The field of Holocaust studies relies on a wide variety of archives, dispersed all over the world. Identifying the right sources for a specific research question within this field is not easy or straightforward. Yet Holocaust scholars predominately focus on methodologies for source analysis rather than discovery. Archival finding aids are among the most important tools to aid primary source discovery, but have hitherto not been considered in methodological discussions on Holocaust research. In this article we will reflect on the composition of finding aids based on our work for the European Holocaust Research Infrastructure (EHRI). Our premise is that the content of finding aids is determined by their authors and the context in which they are creating them. The strongest argument for this subjectivity is that our workoutlined in this article -not only indicates that descriptions of one and the same source differ, but that they can do so quite considerably, and hence can influence research. Our stance is that historians optimize their profit from finding aids by becoming more sensitive to the subjectivity and authorship of descriptions. We conclude by showing how an online environment such as the one developed by EHRI can sensitize historians and archivists to the situated and subjective nature of finding aids by accommodating a plurality of descriptive voices, and encourage them to share their knowledge and become co-authors of finding aids.