Background: Multiple services are often needed to address the needs of young people with complex emotional or behavioural needs. The Youth Wraparound model of service aims to provide all health and supportive services from one coordinating agency. While this has been researched overseas, there are currently few examples of this described in the Australian psychiatric context. Aim: To document the implementation and evaluation of a Youth Wraparound service which was provided to a young person with exceptionally complex and challenging needs for 6 months. A single-case study design is presented with an evaluation of the clinical outcome and economic costs. Methods: We present a description of the service context, principles of the model of care, implementation process, and an evaluation of service utilization data from health and child protection services and mental health records. A single-case longitudinal design compared service utilization data obtained up to 3 years prior to treatment with data collected one and a half years since treatment commenced. Results: There were significant reductions in the number of admissions to emergency departments, mental health wards and secure units, and improvements in mental health and well-being. Yearly average time in institutional settings reduced from 69% to 7%. Cost savings in health utilization were estimated at $2 326 790. Conclusions: The Youth Wraparound model has the potential to offer improved clinical outcomes, significant cost savings over time, improved coordination between care providers, and an alternative to detention or incarceration.