Ordinary Genomes is an ethnography of genomics, a global scientific enterprise, as it is understood and practiced in the Netherlands. Karen-Sue Taussig’s analysis of the Dutch case illustrates the broader phenomenon of the entwining of scientific knowledge and culture: genetics may transform society, but society also transforms genetics. Taussig argues that in the Netherlands, ideas about genetics are shaped by two highly valued and sometimes contradictory Dutch social ideals: a desire for ordinariness and a commitment to tolerance. They are also influenced by Dutch history and concerns about immigration and European unification. Taussig contends that the Dutch enable a social ideal of tolerance by demarcating and containing difference so as to minimize its social threat, and that it is within this particular ideal of tolerance that they construct and manage the meaning of genetic difference. Illuminating the connections between biology, citizenship, and identity, Taussig traces the everyday experiences of Dutch people as they encounter genetics in research labs, clinics, the media, and elsewhere. She explains the institutional framework—involving clinics, research and diagnostic laboratories, and counselling offices—within which human genetic knowledge and practices are produced in the Netherlands. Through her vivid descriptions of specific diagnostic processes Taussig illuminates the open and evolving nature of genetic categories, the ways that abnormal genetic diagnoses are “normalized,” and the ways that race, ethnicity, gender, and religion inform diagnoses. Addressing broader concerns about the interconnections among science, technology, bodies, and the nation, she examines how the Dutch people attempted to come to terms with a transgenic bull (a bull with a gene from another species incorporated into its genome). Taussig’s analysis of how genomics is understood and practiced in the Netherlands challenges monolithic notions of western modernity and of genetics.