»Whistleblower Systems in the Light of the EU Directive 2019/1937 with Special Reference to Assurances of Confidentiality«: Insiders often play an important role in solving crimes. Particularly in the area of white-collar crime, where a large number of unknowns can be assumed, law enforcement agencies rely on information from insiders. Whistleblowers have played a significant role in the initial discovery and subsequent clarification of many recent major scandals. However, potential whistleblowers have so far enjoyed only inadequate protection. In this respect, the EU -Whistleblower-Directive should bring improvement and eliminate legal uncertainties.