AbstractArchaeological developments in the zone extending from Mesoamerica to the Andes are summarized in terms of the following topics: early man, the origins of agriculture, the interrelationships of the Nuclear American cultures, the ethnic identification of archaeological complexes, horizonal and tradition formulations, the place of Nuclear America in the hemisphere, relationships between the New World and the Old World, the rise of native American civilizations, and main trends since 1935. These trends include increasing chronological control, greater awareness of context, growing interest in culture process, and more clarity and precision in definitions.