Much focus is now on delivering enhanced mental health care to youth at ages closer to the onset of the major anxiety, mood or psychotic disorders. However, few health systems have ever been designed to meet the level of demand for such services, or to focus on delivering the range of interventions that could result in enhanced and multidimensional (e,g symptom resolution, improved psychosocial function, reductions in risk of harm) outcomes. When designing new systems of care, much emphasis has been placed on recognition of specific diagnostic categories (e,g psychosis or bipolar disorder) rather than meeting the needs of individuals for comprehensive clinical and psychosocial assessment and ongoing coordinated and measurement-based care. As a consequence of new digital technologies, and new dynamic modelling methods for system planning, we have an opportunity to develop 21St Century responses to these challenges – and to deliver care to a much greater proportion of young people who are otherwise at serious risk of poor outcomes.