From 1962-1966, vertical distribution ozone measurements were made at 11 sites operated or supported by the Environmental Sciences Services Administration in the Western Hemisphere and in Antarctica. Observations made initially at several of the stations to provide information on instrument performance were followed by a major effort in data gathering during the International Quiet Sun Years (IQSY), 1964-1965. This first volume presents results, in the form of ozonagrams displaying ozone and temperature profiles, from the Western Hemisphere stations. Antarctic data will appear in Volume II. Supplementary data--coded values of ozone, temperature, and wind, applicable to standard and significant levels for all soundings--appear in O̲z̲o̲n̲e̲d̲̲a̲t̲a̲f̲̲o̲r̲t̲̲h̲e̲W̲̲o̲r̲l ̲d̲, published by the Meteorological Branch, Canadian Department of Transport. Computer tabulation sheets for IQSY Regener chemiluminescent ozonesonde data are available from the National Weather Records Center, Asheville, N.C.