This article explores the changing relationship between family historians and libraries. Written from a sociological perspective, it tracks changing trends in the kinds of family and social histories that libraries make accessible and family historians pursue. Looking back at library services in past decades, it can be seen that libraries, as well as genealogical societies, once qualified access to information according to social conventions of propriety. However, in recent times, libraries have increasingly democratised their services and accommodated family historians, just as family historians have begun to unearth more diverse, ‘common,’ and concealed histories. Drawing together a range of sources – including memoir, library user survey results, and contemporary sociological studies – the paper examines how cultural institutions have affected and responded to changing preferences in family history research.