The new medical device regulation EU MDR 745/2017 in the European Union has a lot of new requirements. This new regulation is also stronger connected to the EN ISO 13485:2016. The understanding of this changes and how to implement is essential to keep your certificates. The first key for the understanding and the implementation of the changes is the knowledge about the interfaces between the EN ISO 13485:2016 and the EU MDR 2017/745. The second key is to understand, which parts of the EU MDR 2017/745 are not covered by the EN ISO 13485:2016. These not covered paragraphs and requirements must be additional implemented into the quality management system since May 2021. The EU Commission publish monthly new guidance documents for deeper understanding of the requirements and to give more clarification about the expectations by authorities and notified bodies.