The focus of this chapter is on the perspectives on human actions that were adopted in HCI and on how these perspectives influenced HCI research. It is argued that, historically, particular views on human actions played a major role in determining the specific research agendas, methodologies, and outcomes of HCI studies. The discussion in this chapter follows a general trend in HCI research toward increasingly more advanced notions on human actions and a respective series of extensions of the scope of the field from users' tasks to meaningful actions in real-life contexts. The implications of the broadened scope of HCI for conceptual analyses, empirical studies, and design explorations are discussed. This chapter concludes with reflections on new conceptual developments, addressing transformative and emancipatory effects of technology on human, and even non-human, beings.