Americans have long embraced the idea of progress as a key element of national identity. Traditionally, the Smithsonian has been a place to see how far humankind has progressed and predict what advances the future will bring. In the late nineteenth century curators helped shape the way Americans thought about progress by building technological collections and exhibitions along an evolutionary continuum from “primitive” to “civilized.” For much of the twentieth century, exhibitions celebrated modern inventions as the pinnacle of human achievement. In recent years, however, the National Museum of American History has followed the American public in rethinking the idea of progress: Progress for whom? What are the costs of progress? Does progress in science or technology always mean social progress? See how objects collected at different times reflect changing views of the role of science and technology in American life.