The long-term preservation of knowledge about radioactive waste and geological repositories poses a particular challenge in the face of social and cultural change. As part of the OECD/NEA initiative “Preservation of Records, Knowledge and Memory across Generations,” the concept of a Key Information File (KIF) was therefore developed. The KIF is a document that provides basic information about a deep geological repository, radioactive waste, and the associated risks in a way that is easy to understand for the public. The document must be reviewed regularly to ensure that it remains up-to-date and understandable.