According to Lynch, in his article Ethnomethodology and History, ethnomethodology offers a rich and valuable resource for studying the in situ production of history. In this article, we seek to lay out a research agenda for a ‘new business history’ that uses ethnomethodology to study ‘history-in-action’. Our aim is to show how an ethnomethodological history can be used to study the practical work of those tasked with ‘making history’. We discuss the value of ethnomethodology for core business history methods, including the production and use of historical archives and written records, the treatment of witness memories, (auto)-biographies and testimonies, and the production of official versions of past events from diverse historical sources of evidence. We conclude by outlining the potential of ethnomethodology as a distinct paradigm of enquiry, which marks it out from conventional social scientific approaches to the relationship between empirical evidence and theory-building, by discussing: (1) the value of studying the practical reasoning procedures used for generating and interpreting historical evidence; and (2) the value of opening up new forms of reflective practice for practitioners within the field.