Published by the American Geophysical Union as part of the Antarctic Research Series, Volume 9.Since the beginning of the International Geophysical Year In 1957, a new phase of scientific exploration has turned Antarctica into a unique laboratory. Earlier concepts of Antarctica had been mainly preliminary, even confused, having been based upon intermittent, noncontemporaneous, and insufficient observations limited mainly to the periphery of the continent. Through programs supported by international activity, a coordinated and well-founded effort has been directed to the observation, analysis, and interpretation of a broad spectrum of geophysical and biological phenomena and processes. Man began to open up new horizons in his quest for understanding and mastery of Nature.