After having discussed the general purpose and background of the IVDR, the new definition of IVDs, and the conformity assessment in light of the new risk classification as well as the role of notified bodies in part 1 of our 3 part series on the entering into force of the EU In Vitro Diagnostic Regulation (EU) 2017/746 (IVDR), we will now (i) explore key changes regarding clinical evidence and post-market surveillance, and (ii) discuss applicable transition periods.