This second edition of the first comprehensive commentary on the IBA Rules of Evidence covers the revised version of these rules which were adopted by the IBA Council on 17 December 2020. Since their issuance in 1999, The IBA Rules on the Taking of Evidence in International Arbitration have gained wide acceptance within the international arbitration community. Both the original Rules and the revisions of 2010 and 2020 were prepared by working groups of international practitioners representing the major common law and civil law legal systems and reflect a harmonization of the evidence-taking procedures commonly used in international arbitration. The authors provide an overview for arbitration lawyers and users on the relevant practice, case law and doctrine, with a particular focus on Swiss arbitration law and current hot topics such as virtual hearings or the burden of proof in document production.