A school's success is largely determined by the effectiveness of its principal--decades of research have made this clear. Less settled is the question of what principals need to know and do to drive positive outcomes in their schools. A recent report funded by The Wallace Foundation provides evidence on the connection between school principals and school outcomes, focusing on research conducted in U.S. schools since 2000 that connects principals to student achievement, absenteeism, teacher turnover, school climate, and other important markers of successful schools (Grissom, Egalite, & Lindsay, 2021). Several important themes emerged, including just how important principals are in driving school outcomes and the commonalities in what effective principals do--interacting with teachers around instruction, building strong climates where teachers collaborate, and managing strategically. The authors also delved into the importance of leading for equity. This article looks at these themes more closely.