Leadership not only matters: It is second only to teaching among school-related factors that affect student learning. And its impact is greatest in schools with the greatest needs, according to a comprehensive review of evidence on school leadership by researchers at the Universities of Minnesota and Toronto. This report, the first in a series that seeks to establish how leadership promotes student achievement, summarizes the basics of successful leadership and sets out what leaders must do — including setting a clear  vision, supporting and developing a talented staff, and building a solid organizational structure — to meet the challenge of school reform.