Book excerpt: Inspiration and Guidance to Develop Collective Teacher Efficacy Collective efficacy, or a shared belief that through collective action educators can positively influence student outcomes, has remained at the top of a list of influences on student achievement in John Hattie’s Visible Learning research. Collective efficacy has been embodied by many educators, though collaboration tends to be focused on building community and relationships, which alone are not enough to move the needle on student achievement. This book contains stories of collective efficacy in schools where it has been actualized in practice, and includes: • Real-world case studies of teams who have fostered and sustained collective efficacy • Practical guidance for building collective efficacy through professional learning designs • Tools that can be adapted for specific needs or local contexts Through these accounts, readers will gain a better understanding of ways to capitalize on the reciprocal relationship between student achievement and collective efficacy by having a clear understanding of what collective efficacy looks like and how it can be accomplished.