The U. S. National Committee for the International Union of Radio Science, URSI/USNC, is part of the Board on Physics and Astronomy of the National Research Council which, in turn, is part of the National Academy of Sciences. This committee is responsible for appropriate U.S. participation in the International Union of Radio Science (URSI) and advises the National Academy of Sciences on all matters concerning U.S. participation in the union. The committee promotes international cooperation in radio science research through contact with national committees in other countries in such matters as planning of URSI meetings and promoting standards in radio science. The committee sponsors National Radio Science Meetings and symposia in the United States and, jointly with the Canadian National Committee for URSI, the North American Radio Science Meeting.