This article draws attention to the fundamental centrality of “action” – i.e. symbolically constituted behavior – for the historical and social sciences. The work of Max Weber and contemporary American historian and theorist William H. Sewell, Jr. are examined, so as to shed light on the debate concerning social science's central subject matter as well as on the implications of this work for sociological and historical theory. The examination of Sewell's view leverages the importance of the concept of action underlying Weber's concept of “social action.” Weber's position on action and social action is of great interest not only to general theory but also to the field of cultural sociology, which has neglected to develop systematically upon the theoretical purchase Weber offers to it.