Boundaries influence how we live, the way we do and see things – but how? What role do boundaries play in effecting disciplinary shifts or stability in turn? And who is excluded when tracing epistemic frontiers and hard notions of relevance? This theme issue discusses the porosity of anthropology's borders and the difficulty of establishing scholarly authority. We set out to reopen the conversation about the permeability of academic boundaries, exploring different conceptual, methodological and historical reconfigurations with and within European anthropologies. We also discuss how the epistemic and institutional boundaries of our discipline are changing, affecting in turn what people can know and with whom, as well as our sense of professional strength and vulnerability.