There is much agreement about the need for continuous improvement in schools but little understanding about how to bring about the changes in thinking and practice needed to support it. This case study describes a professional collaboration in which a strong, experienced teacher leader is able to learn something truly new, which enables her in turn to move persistently struggling students forward and to share the process by which she did so with her colleagues. Analysis reveals three categories of facilitator moves that were critical in prompting the transformation and that may be transferable to varied settings: adherence to precise purposes and goals; focusing and drilling down; and letting go. This study offers a preliminary framework of effective facilitator moves (those that shift teacher thinking and practice in ways that measurably and continuously improve student performance) for further research.