The OECD announced on 28 May 2015 that it has begun work on developing a Multilateral Instrument that will implement the tax treaty-related output of the OECD/ G20 action plan on base erosion and profit shifting (BEPS).

An ad hoc group has been formed to complete the work and more than eighty countries are participating in this group. Substantive work will begin on 5 and 6 November 2015. A number of international organizations will be invited to participate in the work as observers.

Action 15 of the BEPS action plan concerns the possibility of developing a Multilateral Instrument to permit countries to quickly put through amendments to their double tax treaties as a result of the BEPS project. This will enable changes to be made to bilateral tax treaties without the need for lengthy bilateral renegotiation. The mandate to set up the group to implement this proposal was endorsed by the G20 Finance Ministers and Central Bank governors in February 2015.