Positive behavior interventions and supports (PBIS) is an evidence-based framework for preventing and treating challenging behavior in schools and improving overall school climate. The efficacy of this positive, proactive framework has been well established across varying school settings, yet little is known about schoolwide PBIS implementation and sustainability in high-need school contexts. This qualitative study investigated perceptions of the barriers and facilitators to implementing and sustaining PBIS in high-need schools from the perspectives of four stakeholders. A semistructured focus group was conducted with stakeholders from high-need schools with experience in implementing PBIS. Four key categories were identified: (a) perceptions of PBIS outcomes, (b) challenges, (c) additional supports, and (d) suggestions for improving PBIS in high-need schools. Practical implications and next steps are discussed.