The article is about international courtesy principal evolution and significance. Comitas gentium is not so much teaching on recognition of foreign laws effect, based on individual discretion of sole judge, some influential publications are in support of that standpoint, rather this is basic concept of margins of foreign law force in national legal order. The contrary allegation leads to legislative faults. The author asserts that comitas gentium is the principal of international law compulsory for states but not only directly applicable by discretionally power of judge or arbitrators. That may bring chaos for judicial and arbitration practice without explicit statutory indications. The multinational intercourse as costant and steady as commercial activity itself. It in no way becomes primitive and simple in the circumstance of international sanctions and confrontation. Nevertheless, it requires some renovation of statutory and legal support. The system of judicial control set up in the first half of XX century over enforcements of foreign decisions and awards and state legal aid established by conventions need thorough restructuring and improvements. For the time being it lacks the concept of foreign acts recognition without cooperation and performance thereof as well as legislative criteria of legal grounds for non-recognition of acts effecting domestic persons, public interests, state policy. The contemporary authors as well as their predecessors of XIX century seriously believe that explicit mere recognition of oversees resolutions, decisions, dispositions is possible and feasible nowadays.