Results are presented for a network of gravity control bases located at the major airports throughout the United States. This network of bases was established as a means of integrating existing gravity surveys into a unified whole. It provides not only control of data but also a means of checking and adjusting calibration differences to a common standard. The gravity standard used is that determined by measurements with the Gulf compound quartz pendulum apparatus at a series of sites covering a range of 4,800 mgals between Fairbanks, Alaska, and Mexico City, D. F., Mexico. The accuracy of the individual measurements on an absolute basis is believed to be within 0.3 mgal using a Potsdam datum value of g equal to 980.1190 gals taken at floor level in the United States Coast and Geodetic Survey gravity vault in the Commerce Building, Washington, D. C. Observation sites are described with sufficient detail to permit reoccupation within 5 to 6 feet.