A suicide cluster refers to a ‘group of suicides or suicide attempts, or both, that occur closer together in time and space than would normally be expected on the basis of statistical prediction or community expectation’ (O'Carroll et al, 1988). Although suicide clusters are relatively rare, they receive a lot of attention. This report focuses on suicide clusters in school-aged children. Based on a literature and policy review, the report aims to: • describe the phenomenon of suicide clusters in school-aged children • examine risk factors relating to cluster suicides • describe evidence-based prevention and postvention1 strategies, and review existing youth suicide prevention strategies in NSW. The first part of the report (sections 2 and 3) involves an overview of suicide clusters – including a systematic literature review of suicide clusters in school-aged children, with a description of the studies. The second part (section 4) includes a summary of available evidence. This includes an overview of literature about the impact of internet and social media on suicidal behaviour, postvention strategies to reduce suicide, and current NSW prevention programs and resources. The final part (section 5) concludes that there are comprehensive activities and guidelines available in NSW. However, it is imperative that these guidelines are implemented within a framework that allows their effectiveness and feasibility to be evaluated. The literature review identified that: • Adolescents and young people are at higher risk of suicide clusters than adults. • Suicide clusters in school-aged children and young people have a number of shared characteristics. These include direct or indirect links to other cluster members, communication about other cases by word of mouth and social media, mental health and substance – including alcohol – use problems, relationship problems, frequent use of the internet, and living in a very deprived area. • The underlying mechanisms of suicide clusters are still debated – with the concepts of contagion, modelling, and imitation or assortative relating noted as potential reasons behind suicide clusters. Although limited research has addressed the topic of preventing suicide clusters and specific postvention activities, a set of postvention guidelines has been developed by Cox et al (2016) for schools to use after the suicide of a student. These guidelines outline 20 separate actions – such as developing an emergency response plan, liaising with the deceased student’s family, informing other students and their parents of the suicide, identifying and supporting high-risk students, dealing with the media, and doing a critical incident review. A review of postvention activities in NSW showed that comprehensive activities and guidelines for postvention and prevention have been developed for school-aged children by the NSW Government in collaboration with research and community organisations. A good example is the ‘Responding to Student Suicide – Support Guidelines for schools’ developed in collaboration with the NSW Ministry of Health, NSW Department of Education and headspace (NSW Government, 2015). These guidelines supplement existing initiatives that support the mental health and wellbeing of school students in NSW by enabling a comprehensive and timely response and facilitating holistic support for the entire school when a student dies by suicide. The review highlights the benefits of ongoing collaboration among relevant organisations and researchers, and notes that current postvention activities and guidelines for school-aged children in NSW are following current best practice in the field. The review also notes, however, that more research is needed to better understand the underlying factors of cluster formation and effective ways to prevent them occurring in the future.