Background and purpose: Relatively little research has been conducted on methodology within Cultural-Historical Activity Theory (CHAT). CHAT is mainly used as a framework for developmental processes. The purpose of this article is to discuss both focuses for research and research questions within CHAT and to outline methodologies that can be used to answer these research questions and, thus, to contribute to school-based development. Main argument: Research using the activity system as the starting point can contribute knowledge about the situation before and after an intervention, whereas research using the expansive learning cycle and the research and development (R&D) model as the starting point can present knowledge about the mediated goal-directed actions taking place when members of a community act on the object. Various methodologies can be used in this research. Sources of evidence and method: The article presents a review of methodological articles referred to by Engeström and Sannino ("Educational Research Review", 5 (1): 1-24, 2010) in their overview of methodology in CHAT. There is also a discussion of the research approaches and possible focuses emerging from the author's own research within CHAT, in particular, the activity system, the expansive learning cycle and the R&D model. Conclusion: The article presents new knowledge relating to research focuses and methodologies within CHAT, which will have implications for the way in which research is conducted and used in the further development of practice in school. It is suggested that this knowledge can be a tool for future R&D work.