In the context of implementing a physical activity policy as part of a national school reform in Denmark, the purpose of this study was to explore lower secondary teachers' interpretations and perceptions of the physical activity policy with a focus on movement integration. In total, 14 teachers from four different schools were selected to take part in this qualitative study, which involved semi-structured interviews, focus group interviews, go-along observations and informal interviews. A thematic analysis framework was employed to identify and describe patterns of meaning within data. The findings showed substantial diversity among teachers' interpretations and perceptions of movement integration, and consequently a lack of definitional clarity regarding movement integration and a possible misalignment between policy and practice. Teachers' perceptions and interpretations of movement integration were influenced by other and more prioritised policies and discourses regarding academic achievement, as well as by intrapersonal, interpersonal and institutional factors. The findings also suggested a lack of support and collaboration within the school and provided insights into the strengths and weaknesses associated with the autonomy afforded in the Danish school reform.