In this article, we examine assessment practices during the school placement component of teacher education, focusing on how school-based placement supervisors evaluate and report information about student teachers’ professional skills to the university. While previous studies have shown that universities employ various methods to collect such information, this research has predominantly emphasised oral discussions. This study investigates how supervisors articulate student teachers’ professional skills in written evaluations, which serve as the basis for grading. Theoretically, the study is grounded in Ball’s theory of policy enactment. A qualitative thematic analysis was conducted on 62 written assessments from the final placement of a preschool teacher education programme at a university in Sweden. The findings reveal that the supervisors highlight professional skills by: (1) referencing students’ development over time, (2) drawing on their own interpretations of professional competence, (3) aligning with learning objectives and assessment criteria, and (4) describing how students demonstrate the competencies outlined in these frameworks. The study shows that supervisors are enacting policy in diverse ways that results in varying degrees of consistency and legal certainty in the assessment of student teachers’ placement performance.