Michael Yudell's work seeks to document historically stigmatized populations, the challenges they face in public health and medicine, and how this history affects contemporary health challenges. His book Race Unmasked: Biology and Race in the 20th Century is a history that examines the way in which biologists and geneticists shaped the race concept during the 20th century, from eugenics to the sequencing of the human genome. The book pays careful attention to the ways in which scientific conceptions of human difference affect both public health and medicine. Additionally, the work has important implications for bioethics and public health ethics given race’s role in patient care and in our understandings of the health of populations.