Reflective supervision (RS) has been viewed as best practice and is therefore incorporated--and often mandated--as a key feature of many relationship-based infant and early childhood serving programs. To promote the implementation of high-quality RS for infant and early childhood professionals, it is critical that a focus is placed on "how" infant and early childhood professionals are trained to build RS capacities. To this end, we describe Rhode Island, United States's journey developing, implementing, and iteratively adapting an RS professional development series. We describe the structure of the curricula as well as the content and learning objectives, which strive to bridge the gap between the theoretical concepts foundational to RS, process-oriented self-reflection, and the practical application of RS skills and strategies. We also outline the development and process of iterative adaptation that has refined the curricula over the past decade. Finally, we chronicle the history of coordination and collaboration that promoted the development and implementation of this series, which has been disseminated within home visiting and early care and education settings. This narrative can serve as a model for organizations, systems, and states that are undertaking efforts to provide professional development focused on RS.