In this paper, the concept of international treaty in contemporary international law is being analyzed. The concept of international treaty is being reviewed to international as well as to national extent of Lithuania and some other countries, applying the national law of different countries and international law, which define the concept of international treaty. The subject of the research – the main features of an international treaty, advantages and disadvantages of its consolidation in national and international law. The main objective is, by analyzing literature and the practice of courts, to reveal the concept of contemporary international treaty to international and national extent, and to reveal the advantages and disadvantages of international documents, which consolidate the main elements of an international treaty, as well as to find an optimal opportunity to sort out the problem of an ambiguous concept of international treaty. Appealing to the main instruments of international law, the major features of an international law are revealed: it must be an international agreement; it must governed by international law; it must be made in written form; concluded between States or international organizations; embodied in a single instrument or in two or more related instruments; whatever its particular designation. In the paper a problem of insufficient revelation of the main features of an international treaty in international law is analyzed. One more feature of an... [to full text]