Purpose:This study focuses on school leaders’ daily practices, decisions, and understandings to illuminate the role that distrust plays in school co-location in Denver. In order to inform decisions about the policy's implementation, we examine the relationships between structural dimensions of co-location policy and the ways that school leaders characterize and shape interactions between teachers and students in co-located schools. Research Methods: Drawing from a larger qualitative study, we conducted in-depth, semi-structured interviews with leaders of co-located schools in Denver to explore school leaders’ perspectives and experiences related to school co-location. We analyzed 11 school leaders’ experiences on 7 focal “shared campuses”–buildings housing more than one K-12 school–to identify their understandings of, experiences with, and responses to school co-location. Findings: Although leaders on all focal campuses attempted to keep school communities separate within co-located buildings, most still reported that conflict arose between staff and students from different schools. In some cases, leaders facilitated collaboration between schools, bringing some of the intended benefits of school co-location to fruition. More often they cited competition, which was incentivized by the district's policy of school choice, as a barrier to such efforts. Our data suggest that structural distrust embedded in the policies and processes surrounding school co-location shaped both these everyday interactions among school communities and the opportunities that school leaders saw (or didn’t see) for positive outcomes. Implications: Remedies available to those in authority–including policymakers and school leaders–require that they explicitly acknowledge distrust and change the power imbalances present among stakeholders in co-located schools.