This edited collection disrupts tendencies in feminist science studies to dismiss rhetoric as having concern only for language, and it counters posthumanist theories that ignore human materialities and asymmetries of power as co-constituted with and through distinctions such as gender, sex, race, and ability. The eight essays of Feminist Rhetorical Science Studies: Human Bodies, Posthumanist Worlds model methodologies for doing feminist research in the rhetoric of science. Collectively they build innovative interdisciplinary bridges across the related but divergent fields of feminism, posthumanism, new materialism, and the rhetoric of science. Each essay addresses a question: How can feminist rhetoricians of science engage responsibly with emerging theories of the posthuman? Some contributors respond with case studies in medical practice (fetal ultrasound; patient noncompliance), medical science (the neuroscience of sex differences), and health policy (drug trials of the U.S. Food and Drug Administration); others respond with a critical review of object-oriented ontology and a framework for researching women technical writers in the workplace. These contributions are in turn framed by a comprehensive introduction and a final chapter from the editors, who argue that a key contribution of feminist posthumanist rhetoric is that it rethinks the agencies of people, things, and practices in ways that can bring about more ethical human relations. Individually the contributions offer as much variety as consensus on matters of methodology. Together they demonstrate how feminist posthumanist and materialist approaches to science expand our notions of what rhetoric is and does, yet they manage to do so without sacrificing what makes their inquiries distinctively rhetorical.