Bullying and cyberbullying are global phenomena negatively impacting on children's and young people's (CYP's) mental health and wellbeing and affecting their school social experiences and learning outcomes. Many interventions and prevention approaches have been employed over the decades, most impacting differentially, with some success in certain contexts and situations but not universally, suggesting the need for more contextualised, nuanced approaches at the whole school, community, individual and peer-group levels. The recognition of the importance of student and teacher voice in recent years has heralded interest in co-design practices to deliver more context-relevant interventions and prevention strategies. This article considers how participatory design and co-design practices can form part of the prevention and intervention repertoire for schools, teachers, counsellors and psychologists in their quest to understand and reduce cyberbullying and/or bullying (C/B) behaviours. Two case-study exemplars are provided that reflect the importance of context and student-centred relevancy to inform practice.