Video study is a complex methodological approach, which enables the employing of various strategies, methods or techniques for generating, collecting and analysing video data, i.e. audiovisual data grounded in rich situational contexts. Section I focuses on the power of video to describe the dynamics of teaching and learning in the classroom. It presents various video studies conducted in the past fifteen years that aimed to describe the practices of teaching. Section II focuses on the use of video in investigating the effects of teaching on student learning. The chapters present approaches that build on video studies in order to link data about classroom processes with data about learning outcomes. The chapters in section III discuss possibilities offered by the use of video in professional development of teachers.
