The Vienna Convention on Succession of States in Respect of Treaties is an international treaty opened for signature in 1978 to set rules on succession of states.

It was adopted partly in response to the "profound transformation of the international community brought about by the decolonization process".

It entered into force on 6 November 1996, which was triggered by the succession of the Republic of North Macedonia to the treaty giving it the requisite 15 parties.

[1] The treaty has proven to be controversial largely because it distinguishes between "newly independent states" (a euphemism for former colonies) and "cases of separation of parts of a state" (a euphemism for all other new states).

As of February 2019, there are 23 state parties which have ratified the convention.