Given the predictive nature of high-quality early childhood programs on children's social and learning outcomes, effective leadership is critical to facilitate program improvement. Recognizing the need for cohesive conceptual frameworks that undergird research-based practice, a 5-year training institute for early childhood program directors was evaluated to assess training effectiveness. Moreover, we developed a model of early childhood leadership professional development grounded in our iterative analysis of data from this study and guided by theory-building methods. The findings show positive impacts on leaders' self-reported facilitation and implementation of developmentally appropriate strategies in positive discipline and prosocial skills in early care and education settings. The practice-to-theory training model developed provides a theoretically cohesive framework to guide the professional development of early childhood program leaders that repositions the theory/practice binary by helping leaders problematize issues of practice and infuse theory as necessary tools and pragmatic anchors for solving real-world problems.