By September 2014, it was clear that conventional approaches to containing the spread of Ebola in West Africa were failing. Public health teams were often met with fear, and efforts to treat patients and curtail population movement frequently backfired. Both governments and international agencies recognized that anthropological expertise was essential if locally acceptable, community-based interventions to interrupt transmission were to be designed. The Ebola Response Anthropology Platform was established against this background. Drawing together local and internationally based anthropologists, the Platform provided a coordinated and rapid response to the outbreak in real time. This social thought & commentary piece explores how the Platform developed and interacted with other epistemic communities to produce knowledge and policy over the course of the outbreak. Reflecting on the experiences of working with the UK Department for International Development, the World Health Organization, and other agencies, we ask: what do these experiences reveal about the politics of (expert) knowledge and its influence on the design and implementation of policy? Did differing conceptions of the place of anthropology in humanitarian crises by policymakers and practitioners shape the contributions made by the Ebola Response Anthropology Platform? What are the implications of these experiences for future anthropological engagement with, and research on, humanitarian responses to health crises?