The aim of this video is to introduce the cultural-historical activity theory (CHAT). CHAT is a research paradigm that comprises a wide range of conceptual resources, methods, and models for conducting a specific type of research. It produces contextual knowledge to the needs of communities and can be used in practical interventions aiming at understanding and improving human activities especially in work contexts. Speaker: Virpi Lund Manuscript and content planning: Virpi Lund and Soile Juujärvi Video production: Jonne Piltonen This video has been producted by the project of Empowering People towards Socially Sustainable Society in the Laurea University of Applied Sciences. The project is funded by the Ministry of Education and Culture. Editorial board for publishing open educational resources at Laurea is responsible for the editorial work of the video.