Background Schools need mental health interventions that are deliverable, scalable and effective. However, rates of successful implementation of evidence-based practices in schools is low. An underpinning factor is lack of understanding, and attention, by commissioners, providers and schools, to evidence about what works to bolster effective and sustained implementation. Knowledge brokering is one way to improve use of implementation science for delivery of interventions in complex settings. To date, evidence for the use of knowleldge brokers in public health settings is scarce, and their use for brokering implementation related knowledge is non-existent. The aim of this study was to examine whether it was feasible and acceptable for knowledge about implementation to be brokered to a steering group responsible for a wide scale, public mental health, school-based intervention, and what impact this might have on their implementation decisions.Methods The primary researcher attended 13 monthly steering group meetings during the initial implementation phase of the public mental health program and shared implementation knowledge with them. With consent, meeting notes were taken by the primary researcher, and a journal kept of 12 meetings; 5 meetings were also audio recorded and steering group minutes analysed. All data were amalgamated and ordered into month-by-month summaries. The analysis attempted to identify when implementation knowledge was shared with the group (coded a ‘key moment’) and what the steering group did with this knowledge (coded a ‘key outcome’).Results Over the 13 meetings, 15 key moments led to 14 key outcomes, 10 of which involved implementation decisions being made based on brokered knowledge about implementation science. Discussion The majority of key moments led to a significant number of evidence-informed implementation decisions being made by the steering group. Some brokered knowledge was not acted upon. Implementation knowledge was not shared with the program funders which may have meant they did not appreciate the importance of implementation. Conclusion Knowledge brokering on implementation science to a group responsible for public mental health is feasible and acceptable and a potentially viable implementation strategy for future public health programs.