On October 24, 1945, the National Research Council (NRC) of Canada convened the first meeting of an Associate Committee to advise it on the needs of geophysics, with J.T.Wilson as the Chairman of the committee. In 1946, this committee was amalgamated with the Canadian committee for the International Union of Geodesy and Geophysics (IUGG) to form the Associate Committee of Geodesy and Geophysics (ACGG) of the NRC. Activities of geophysicists in Canada were coordinated by ACGG by forming a number of subcommittees. In 1974, the ACGG was replaced by a professional society called "The Candian Geophysical Union, a joined Division of the Geological Association of Canada (GAC) and of the Canadian Association of Physicists (CAP)", and with J.T.Wilson as its first president. The Canadian Geophysical Union became an independent organization in 1988, but today geophysicists still can join CGU by joining CAP or the Geophysics Division of GAC. In 1993, the CGU formed a Hydrology Section. Now with about 500 members, CGU serves as the national focus for geophysical sciences and carries on the traditional responsibility of representing Canada in the IUGG through a Canadian National Committee (CNC/IUGG).