While radar, ARPA, and other technological developments, together with better training of ship's officers in their use, have substantially reduced the frequency of collisions and strandings, they have by no means eliminated them. Navigation has been simplified to some extent by the adoption of two major codifications: (1) The International Regulations of Preventing Collisions at Sea (COLREGS), the first thorough revision since the International Rules were formulated at the Washington Conference of 1889, and (2) the Inland Navigation Rules, effective throughout the United States in place of the old Inland, Great Lakes, and Western Rivers Rules. The United States law in both-to-blame cases has been brought into closer harmony with that of the other maritime countries by adoption of the proportional fault rule in United States v. Reliable Transfer Co., perhaps the most significant decision in the area ever rendered by the United States Supreme Court.