The Fifth Assembly of the International Union of Geodesy and Geophysics was held at Lisbon, Portugal, September 17–26, 1933. The Association of Geodesy, with a longer program of reports and discussion than the other associations, began its meetings three days before the official opening of the Assembly, September 17.The meeting was attended by 178 official delegates and guests; this number does not include the wives and friends accompanying the delegates and guests. Official delegates represented 21 of the 37 countries adhering to the Union as Followst Belglum, Bulgaria, Canada, Czechoslovakia, Denmark, Finland, France, Great Britain, Greece, Italy, Japan, Morocco, Netherlands, Norway, Poland, Portugal, Spain, Sweden, Switzerland, United States, Yugoslavia. Countries not yet adhering to the Union, represented by invited guests, were British India, China, Germany, and Venezuela. Thus the total number of countries represented at this Assembly was 25. The United States was represented by six delegates, namely, Walter D. Lambert, James B. Macelwane, S.J., Harry D. Harradon, John A. Fleming, and Thomas G. Thompson, who represented the National Academy of Sciences and the National Research Council, and David McD. Le Breton who represented the Hydrographic Office of the United States Nav