VISION: Our vision is to harness the potential of digital technology to transform adolescent mental health and wellbeing and provide a safe, and supportive, digital environment to tackle the growing humanitarian crisis of unmet need arising from mental health disorders in young people (covering the definition of adolescence from age 10 up to the age of 25). THE PROBLEM: There is a youth mental health crisis; in the UK, 1.25 million (25%) of 17-19-year-olds experience significant levels of depression or anxiety; yet less than a third of these young people receive any treatment. Academic-led digital interventions exist but few, if any, have been implemented in real-world settings. Meanwhile, there are thousands of mental health and wellbeing apps, but the vast majority have no evidence-base and some may be harmful. This crisis coincides with a new 'digital environment', where being online and using social media has become integral to young people's lives. However, social media platforms are not designed to meet the mental health needs of young people. Pressing societal, public policy and research questions concern how the 'digital environment' affects young people's mental health; whether it increases the risk for mental health problems and how vulnerable young people with mental health difficulties engage with the digital environment. THE SOLUTION: Our research vision addresses two key challenges: i) RESEARCH THEME 1: DIGITAL INTERVENTIONS: How to harness digital technologies and platforms to identify those at risk and target personalised digital interventions that bridge the adolescent mental health treatment gap. This includes developing the infrastructure to collect, share, discover and analyse sensitive personal data that matches the speed of digital innovation ii) RESEARCH THEME 2: DIGITAL RISK & RESILIENCE: How engagement with the digital environment influences, and is influenced by, adolescent mental health problems, brain and cognitive development and what factors promote resilience. We aim to generate evidence-based advice to safeguard youth from harmful digital environments and design tools to promote resilience. ENGAGEMENT STRATEGY: We will bring together, through workshops, knowledge exchange events and pilot studies, an interdisciplinary community of researchers (psychiatry, psychology, neuroimaging, computer science, arts & design, humanities, education) to work with young people, parents/caregivers, clinicians, digital technology developers and policy-makers to offer vital co-ordination and research leadership in this nascent field. The collaboration builds on an outstanding track record of digital mental health research at the University of Nottingham (UoN) (NIHR MindTech Medtech Co-operative, NIHR Nottingham Biomedical Research Centre Mental Health & Technology Theme and Horizon Digital Economy Research Institute). We will engage with industry and charity partners (BBC, Xenzone, Samaritans), leading UK academic centres (Oxford, UCL, KCL, LSE) and UKRI Mental Health Networks (eNurture, Emerging Minds). YOUTH ENGAGEMENT: Young People's Advisory Group (YPAG): working in collaboration with McPin Foundation we will ensure that immersive patient and public involvement (PPI) and co-production with young people and their parents/caregivers cuts across all of our activities. Our Partners Board will facilitate knowledge exchange with healthcare, social care, education, policy-makers and industry to deliver evidence-based policy and practice solutions that can be readily implemented. OUTPUTS & IMPACT: Our proposed Engagement Award will be at the vanguard of these developments through building and sustaining new interdisciplinary research collaborations, knowledge exchange, developing early career researchers (ECRs), engaging new partners and laying out a road map for future research.