The Multimodal Approach to Preventing Suicide in Schools (MAPSS) is an Australian intervention for schools consisting of a psychoeducation session on suicide alertness, screening to identify students at risk, and an online cognitive behavioural therapy intervention for students who disclose suicidal ideation. We have recently introduced MAPSS in UK schools as part of a randomised controlled trial, following a successful scoping study and pilot evaluation. However, resources needed to be adapted and updated following feedback from young people, to ensure its validity in a UK setting. We worked with young people, parents, school staff, mental health professionals, and adults with lived experience in an iterative process to identify the adaptations needed for MAPSS, and to co-produce new resources for a UK-based trial. We conducted semi-structured interviews with professionals (N=16) and parents (N=3), as well as focus groups with young people (N=27) aged 15-18, to understand what adaptations would need to be made to existing MAPSS resources. We then established advisory groups with young people (N=20) and adults with lived experience (N=5) in collaboration with local voluntary community organisations. The purpose of the focus group was to: • Understand different perspectives and ensure resources are relevant and address real needs, • Identify gaps and barriers relating to issues young people are having when trying to access support, • Build trust and collaboration by engaging with the community, • Enhance the effectiveness of MAPSS to co-produce authentic, age-appropriate, culturally sensitive resources. The process of co-production and the new materials were then shared at a public engagement and dissemination workshop, to ascertain further feedback and necessary changes. In this symposium, we will share the new resources and reflect on our experiences, including areas of innovation and facilitators and barriers to co-production with young people in the field of suicide prevention.