The mainstream framework for human-computer interaction (HCI) research, based on information processing cognitive psychology, has faced increasing criticism due to its limitations in both research and practical design. This chapter discusses the potential of activity theory as an alternative framework for HCI research and design. Despite the apparent harmony in HCI, research and practice are not aligned, with researchers struggling to provide grounded advice for interface development. There is a significant gap between research results and practical design, as many designers are unaware of HCI research and its findings. HCI research often lacks coherence and context sensitivity, leading to fragmented guidelines. A debate emerged in the late 1980s against the use of information processing psychology as the foundation of HCI, leading to a crisis in the field. This is evident in the contrast between two collections of HCI research articles published in 1987 and 1991. The latter reflects a more critical view of information processing psychology and a shift toward more comprehensive approaches. Liam Bannon identified several issues in mainstream HCI research, including the reduction of humans to passive components, the use of predetermined requirements, the reliance on laboratory experiments, and the focus on inexperienced users. He proposed a shift toward considering humans as active actors, groups, and processes, as well as the importance of iterative design and user involvement. Jonathan Grudin and others recognized the need for a broader, more integrated approach to HCI research, moving beyond the technical level to consider conceptual and work process levels. Activity theory, rooted in Soviet cultural-historical psychology, offers a framework that emphasizes the dynamic, contextual, and social aspects of human activity. It views activities as complex, evolving processes involving individuals, tools, and communities, with a focus on mediation, historical development, and the interplay between subjects, objects, and communities. Activity theory provides a philosophical and cross-disciplinary framework for studying human practices as development processes. It emphasizes the importance of context, the role of artifacts and tools, and the dynamic nature of activities. The theory suggests that activities are not static but are continuously changing and developing, influenced by contradictions and the need for adaptation. Activity theory also highlights the relationship between activities and information technology, noting that IT can support activities at various levels, from automating operations to facilitating sense-making and communication. The theory offers a multilevel perspective, emphasizing the importance of context, interaction, and development in HCI research and design. It suggests that activity theory could provide a valuable framework for addressing the complexities and challenges in HCI research and design.The mainstream framework for human-computer interaction (HCI) research, based on information processing cognitive psychology, has faced increasing criticism due to its limitations in both research and practical design. This chapter discusses the potential of activity theory as an alternative framework for HCI research and design. Despite the apparent harmony in HCI, research and practice are not aligned, with researchers struggling to provide grounded advice for interface development. There is a significant gap between research results and practical design, as many designers are unaware of HCI research and its findings. HCI research often lacks coherence and context sensitivity, leading to fragmented guidelines. A debate emerged in the late 1980s against the use of information processing psychology as the foundation of HCI, leading to a crisis in the field. This is evident in the contrast between two collections of HCI research articles published in 1987 and 1991. The latter reflects a more critical view of information processing psychology and a shift toward more comprehensive approaches. Liam Bannon identified several issues in mainstream HCI research, including the reduction of humans to passive components, the use of predetermined requirements, the reliance on laboratory experiments, and the focus on inexperienced users. He proposed a shift toward considering humans as active actors, groups, and processes, as well as the importance of iterative design and user involvement. Jonathan Grudin and others recognized the need for a broader, more integrated approach to HCI research, moving beyond the technical level to consider conceptual and work process levels. Activity theory, rooted in Soviet cultural-historical psychology, offers a framework that emphasizes the dynamic, contextual, and social aspects of human activity. It views activities as complex, evolving processes involving individuals, tools, and communities, with a focus on mediation, historical development, and the interplay between subjects, objects, and communities. Activity theory provides a philosophical and cross-disciplinary framework for studying human practices as development processes. It emphasizes the importance of context, the role of artifacts and tools, and the dynamic nature of activities. The theory suggests that activities are not static but are continuously changing and developing, influenced by contradictions and the need for adaptation. Activity theory also highlights the relationship between activities and information technology, noting that IT can support activities at various levels, from automating operations to facilitating sense-making and communication. The theory offers a multilevel perspective, emphasizing the importance of context, interaction, and development in HCI research and design. It suggests that activity theory could provide a valuable framework for addressing the complexities and challenges in HCI research and design.