The Convention was adopted on 22 May 1969 and opened for signature on 23 May 1969 by the United Nations Conference on the Law of Treaties. The Conference was convened pursuant to General Assembly resolutions 2166 (XXI) of 5 December 1966 and 2287 (XXII) of 6 December 1967. The Conference held two sessions, both at the Neue Hofburg in Vienna, the first session from 26 March to 24 May 1968 and the second session from 9 April to 22 May 1969. In addition to the Convention, the Conference adopted the Final Act and certain declarations and resolutions, which are annexed to that Act. By unanimous decision of the Conference, the original of the Final Act was deposited in the archives of the Federal Ministry for Foreign Affairs of Austria. Entry into force on 27 January 1980, in accordance with article 84(1). Text: United Nations, Treaty Series, vol. 1155, p.331.