The participation of the federations“ subjects (administrative-territorial units) in external relations is in the centre of attention of the specialists of different kind, lawyers as well. It was actively discussed in the process of elaboration of both Vienna conventions on the law of the treaties of 1969 and 1986, but had no solution there.Trans-border cooperation of the local territorial units is most active. So that to direct it into the civilized course there was adopted the European frame convention on the trans-border cooperation of the territorial associations and authorities of 1980.After the dissolution of the USSR the territorial units of the Russian Federation actively started entering with “external partners” into the treaty relations in economic and other spheres. The modern practice and the due legal basis are analyzed here.Among all the author of this article supports the idea to make the draft Convention on international treaties of the territorial units (the subjects of federations) of states. The materials of the Vienna conference of 1969 on the law of the treaties are of great interest in this question.