This study reflects the voice of school leaders (principals) in a Norwegian school development project focusing on assessment for learning (AfL). The central role of the principal in school improvement is well documented, however, less is written about how the principals themselves see their roles. The voices presented belong to two experienced principals from two elementary schools in Norway. The schools participated in a three-year-action-oriented development project aimed at establishing an AfL culture. Towards the end of the project, the principals shared their experiences in a semi-structured group interview. The findings support the central role principals play in successful implementation of change. However, their role is not sufficiently appreciated and taken into account. (Contains 2 notes.)