The discovery of the two inherited susceptibility genes BRCA1 and BRCA2 in the mid-1990s created the possibility of predictive genetic testing and led to the establishment of specific medical programmes for those at high risk of developing breast cancer in the UK, US and Europe. In the intervening fifteen years, the medical institutionalisation of these knowledge-practices and accompanying medical techniques for assessing and managing risk have advanced at a rapid pace across multiple national and transnational arenas, whilst also themselves constituting a highly mobile and shifting terrain. This unique edited collection brings together cross-disciplinary social science research to present a broad global comparative understanding of the implications of BRCA gene research and medical practices. With a focus on time-economies that unfold locally, nationally and transnationally (including in Brazil, Canada, France, Germany, India, Italy, the UK and the USA), the essays in this volume facilitate a re-reading of concepts such as prevention, kinship and heredity, and together offer a unique, timely and comparative perspective on these developments. The book provides a coherent structure for examining the diversity of practices and discourses that surround developments linked to BRCA genetics, and to the evolving field of genetics more broadly. It will be of interest to students and scholars of anthropology, sociology, history of science, STS, public health and bioethics.