"Transformational Professional Learning" is a periodically published e-newsletter designed to influence what educational leaders think, say, and do to improve teaching and learning by promoting deep understanding of important issues, the transformation of beliefs and assumptions, and a stream of powerful goal-focused actions. There are two articles in this issue. In "Principals as Staff Development Leaders," Dennis Sparks writes that principals play an essential leadership role in planning, implementing, and evaluating the effectiveness of professional learning in their schools. He asserts that what principals think, say, and do has a profound effect on the culture and performance of their schools. In the second article, "The Power of Organizational Culture," Sparks writes that whether what is at stake is student achievement or retention of valued teachers, cultural factors, such as those described in the previous article, cannot be ignored. The knowledge and skills of principals as cultivators of culture are central to creating high performing schools in which both students and employees thrive. He adds that a sidebar to a June 2002 "Training" article on employee retention listing the top ten ways to lose employees could easily be thought of as school culture issues. In both articles Sparks recommends ways to examine one's own assumptions about the issue; deepen one's understanding of the issue; and next action thinking that can be done relating to the issue.