The PROJECT will support young people in maintaining their health in a rapidly changing society. With unique initiatives, we aim at identifying an evidence-based knowledge gap to deepen our understanding of daily life among young people in changing and stressful environments in wide ecosystem (Bio-audit, WP1). Our PROJECT seeks to combine multiple elements of a novel theory-based intervention with AI to promote well-being and health among young people while preventing dysfunction across Europe and beyond. We will adopt and implement evidence-based multi-level intervention, which can be easily implemented and replicated by key stakeholders in diverse countries, both within and outside Europe (The AI-based Intervention, WP2). The impact of the multi-level preventive intervention will be monitored and evaluated in close collaboration with various key stakeholders using non-adverse methods. Feasibility, effectiveness and possible harms of the intervention will be assessed with robust methods (Effectiveness Trial, WP3). Using Simulation Modelling, we will develop a new approach how to implement and scaled up the multi-level preventive intervention in various contexts, taking account rapidly changing societies (Implementation, WP4). Furthermore, we will produce strategies how to conduct comprehensive policy campaigns at various levels of the ecosystem to better equip different stakeholders, local actors, leaders, policymakers, families, professionals in social, and health care and Voir plus