The Annie E. Casey Foundation hired the Leadership Learning Community to explore the viability of bringing an Evidence Based Practice to the field of leadership development. The foundation in interested in how this approach could scale its leadership work and improve the lives of kids and families. Leadership is recognized as a critical success factor in this process. Currently not much is known about evidence-based practice in leadership work. This eight week investigation and analysis has been divided into two phases. The first phase of research summarized in this papers, studies the development of Evidence-Based Research as a methodology with its origins in the field of medicine.