The concept of «teacher as researcher” is several decades old, but creating school cultures and practices that enable teachers to really study and investigate their practices in systematic ways is still not common. In this session, I will present results from schools in Norway that have continuously worked on how to strengthen their culture of research, developing both principals’ and teachers’ skills, practices and the use of research literature. My emphasis will be on processes and experiences from using Lesson Study as a vehicle for school development. Questions I will address are: (1) Why have schools wanted to strengthen their research literacy and research skills? (2) What are the key elements of “teacher as researcher” that are difficult? (3) How have schools been able to maintain focus for more than 10 years? And (4) What role does teacher education and mentoring novice teachers play?