This Science and Society Dissertation Improvement Grant is a multi-sited ethnographic study of pedagogy and training in structural biology that investigates how scientific research institutions in the US are breeding a new kind of life scientist one who is attuned to the structures and functions protein molecules. Lured by the promise of insights into how life works, biologists, chemists, physicists, engineers and computer scientists are converging on the field of structural biology. These researchers recognize that producing and interpreting protein structure data demands craft skills and embodied forms of knowing, and they are currently developing pedagogical forms that aim to make these tacit skills explicit to their students. As the field rapidly expands, and new professional identities are forged, there is a need for close ethnographic attention to research and training in structural biology, observed in situ in the laboratory and in the classroom. NSF funding will support interviews with researchers and students at all stages of their scientific careers, ethnographic observation and video analysis of undergraduate lecture courses and teaching laboratories, and laboratory studies of graduate student and postdoc training in protein visualization techniques. The study will track emerging regimes of training in the arts of molecular visualization. Through dissemination in the form of a dissertation, articles and eventually a book, the intellectual merit of this study lies in its significant and innovative contributions to STS analyses of the role of tacit knowledge, and the multiple modes of reasoning at work in scientific practice; historical and social studies of the visual cultures in science, illuminating epistemological differences between traditions of imaging, modeling and simulation; and methods in the anthropology of science, in particular, by attending to embodiment and performativity in scientific visualization. With regards to its broader impacts, this study is positioned to contribute directly to science education, meeting a need, widely recognized by major funding bodies, that pedagogy, training and mentorship in emergent fields, like structural biology, require constant revision and close study. Through collaborations with top educators, including HHMI Professor Catherine Drennan, and the MIT Museum, this study makes direct contributions to improving both undergraduate teaching and outreach programs for the diverse body of K-12 students in the Cambridge and Boston areas. The study will also contribute directly to debates within the structural biology community. As disciplinarily diverse researchers converge on the task of protein visualization, this analysis will shed light the challenges of interdisciplinary training and make visible the tacit assumptions and modes of reasoning shaping emerging conventions of communication and visualization.