This essay describes historians' recent and growing awareness of the significance of science in modern Latin America. It focuses first on the work and influence of the historian Nancy Leys Stepan, who in the past 30 years pioneered the joining of methods in the history of science — in particular, the tendency to see science in its specific social context — with some of the most central concerns of Latin Americanists. For example, a key contribution of Stepan's work is her analysis of scientific representations of human difference that shaped the creation and legitimating of racist and sexist ideas across Latin American societies. Moreover, her work was part of an early wave that brought the application of feminist and critical race theory to the field, with valuable outcomes. Her work has been a springboard for continuing investigations of the interplay between scientific ideas and practices and larger social forces. After an overview of Stepan's approach and findings, the essay discusses two major trends in the literature that emerge from and build on Stepan's work: the incorporation of sexuality along with race, gender, and class in studies of science and medicine in Latin American history; and further developments in the history of transatlantic science in the modern period.