While considerable evidence indicates that school leaders are able to make important contributions to the success of their students, much less is known about how such contributions are made. This book provides a comprehensive account of research aimed at filling this gap in our knowledge, along with guidelines about how school leaders might use this knowledge for their own school improvement work.  Leadership practices known to be effective for improving student success are outlined in the first section of the book while the remaining sections identify four “paths” along which the influence of those practices “flow” to exercise an influence on student success. Each of the Rational, Emotional, Organizational and Family paths are populated by conditions or variables known to have relatively direct effects on student success and also open to influence by effective leadership practices.  While the Four Path framework narrows the attention of school leaders to a still-considerable number conditions known to contribute to student success, it leaves school leaders the autonomy to select, for improvement efforts, the sub-set of conditions that make the most sense in their own local circumstances. The approach to leadership described in this book provides evidence-based guidance on what to lead and flexibility on how to lead for purposes of improving student learning.