This article reports on a national study examining the characteristics of effective school principals which reveals that high student achievement is directly linked to "collective leadership"--the shared influence of educators, parents, stakeholders, and community members. The five-year study, commissioned by the Wallace Foundation and produced by the Universities of Minnesota and Toronto, is the largest of its kind to unravel the relationship between school leadership and student achievement. "Learning From Leadership: Investigating the Links to Improved Student Achievement," which draws on a survey of 8,000 teachers and administrators, confirmed that school leadership is the second most important influence on student learning, ranking only behind classroom instruction. The research validates the link between leadership and learning. The study finds that principals, assistant principals, and leadership teams working collaboratively with teachers, parents, and communities make a difference in improving performance. The study's key findings and major challenges are presented.