ObjectiveImplementation of effective population-level injury prevention interventions requires broad multiagency partnerships. Different stakeholders address this from varying perspectives, and potential conflicts in priorities need to be addressed for such partnerships to be effective. The researcher-led National Guidance for Australian football Partnerships and Safety (NoGAPS) project involved the engagement and participation of seven non-academic partners, including government health promotion and safety agencies; peak sports professional and advocacy bodies and health insurance organisations.DesignThe partnership's ongoing development was assessed by each partner completing the Victorian Health Promotion Foundation Partnership Analysis Tool (VPAT) annually over 2011–2015. Changes in VPAT scores were compared through repeated measures analysis of variance.ResultsOverall, mean total VPAT scores increased significantly over the 5-year period (125.1–141.2; F5,30=4.61, p=0.003), showing a significant improvement in how the partnership was functioning over time. This was largely driven by significant increases in several VPAT domains: ‘determining the need for a partnership’ (F5,30=4.15, p=0.006), ‘making sure the partnership works’ (F5,30=2.59, p=0.046), ‘planning collaborative action’ (F5,30=5.13, p=0.002) and ‘minimising the barriers to the partnership’ (F5,30=6.66, p<0.001).ConclusionThis is the first study to assess the functioning of a multiagency partnership to address sport injury prevention implementation. For NoGAPS, the engagement of stakeholders from the outset facilitated the development of new and/or stronger links between non-academic partners. Partners shared the common goal of ensuring the real-world uptake of interventions and research evidence-informed recommendations. Effective multiagency partnerships have the potential to influence the implementation of policies and practices beyond the life of a research project.