Purpose: This study sets out to investigate the elements of the collaborative culture required for the successful implementation and sustainability of programs in schools. It draws on a case study of a student peer-led physical activity (PA) program implemented within the complex and dynamic environment of school communities in New Zealand. The article outlines four key components needed to effectively implement and impact long term sustainability of a program within the school context. Design/methodology/approach: This qualitative case study examines the implementation of a new peer-led PA program introduced across eight New Zealand schools. Data were collected from semi-structured interviews with senior leaders, teachers and parents and analyzed through a complexity theory lens. Findings: Effective and sustainable program implementation requires a strategic, collaborative approach through actively engaging with and resourcing four key interacting components: student choice, voice and agency; collective responsibility; shared understanding of purpose; and curriculum coherence. Originality/value: This research offers a pragmatic approach to developing collaborative school communities that can effectively implement change by highlighting key areas of focus that policymaker, school leaders and program designers can plan for.