Although a substantial body of evidence documents the potential effectiveness of the community school strategy, we are still determining why community schools have shown uneven results. To address this gap, we investigate how leaders developed social capital in three established community schools that serve marginalized communities. Drawing on documents, qualitative interviews with principals and community school coordinators, and studies of how they spent their time, we use relational trust theory to analyze the social interactions of school leaders. We find that the schools successfully developed productive partnerships and garnered services and supports to benefit their students and families. Facing differing patterns of leadership turnover and other contextual challenges, however, the schools varied in their abilities to leverage the resources made available to them to equalize student outcomes. Success, in part, stemmed from school and district administrators' abilities to build trusting relationships and align stakeholders' efforts around a cohesive, student-centered vision that addressed the schools' core academic program. The ensuing discussion furthers understandings about shared leadership and trust as levers for school improvement.