The Second World War was a watershed moment in US–South American relations. Yet the Good Neighbor Policy—the driving force behind many of the changes during this time—remains underanalyzed, especially from a South American perspective. Examining topics ranging from literary fashions and trends in the press to science, militarism, and gender categories, New Perspectives on the Good Neighbor Policy sheds light on this crucial period in which the US defined geopolitical relations with South America and solidified its hemispheric hegemony. Additionally, the contributors evaluate the legacy of the Good Neighbor Policy in the twentieth century and its impact on twenty-first century politics.