The requirement of including Key Audit Matters (KAM) is the most significant change made to the auditor’s report in many years. The purpose of KAM is to meet the request from the users of accounting information to include more information in the auditor’s report on matters that are most significant and critical to the audit and, by that, enhancing the transparency and communicative value of the auditor’s report. Still, the KAM disclosure requirement may have both intended and unintended consequences for auditors, clients, users and regulators. Subsequent to the introduction of KAM, a significant number of research papers has explored the impact of KAM or similar reporting initiatives (CAM/RMM/EQM/JOA).2 Our literature review includes research published through May 2020. The review is structured into auditor consequences, user consequences, and client consequences. We carefully distinguish between various extended auditor reporting initiatives, such as KAM/CAM/RMM when discussing the research findings. Based on the archival research, the impact of KAM disclosure appears to be non-existent or at best very small. The experimental research papers focusing on KAM/CAM provide some indications of a behavioral impact. Still, these findings should be interpreted with caution since most of the participants in these experiments are less sophisticated than in a “real life setting”. The research activity in this area is high, and future research could help to further indicate and eventually confirm the various potential implications of the new reporting regime. Based on the available evidence at this point, the overall impact of the KAM/CAM disclosure requirement appears to be limited and, to some extent, mixed.