The Max Planck Encyclopedia of Public International Law (MPEPIL) is an online encyclopedia dealing with international law. It was published under the auspices of Professor Rüdiger Wolfrum, Director of the Max Planck Institute for Comparative Public Law and International Law until his successor Anne Peters became general editor in 2021. The initiative to compile the MPEPIL began in 2004 and the online version launched in September 2008. It represents a new edition of the Encyclopedia of Public International Law published between 1991 and 2001 by Rudolf Bernhardt. In February 2012, the print edition was published by Oxford University Press. The encyclopedia is peer reviewed.