This project will work closely with existing service partners involved in street level services and focus on testing and evaluating three approaches for street level interventions for youth who are homeless and who have severe or moderate mentally illness. Youth will be asked to choose their preferred service approach: Housing First related initiatives focused on interventions designed to move youth to appropriate and available housing and ongoing housing supports. Treatment First initiatives to provide Mental Health/Addiction supports and treatment solutions, and; Simultaneous attention to both Housing and Treatment Together Our primary objective is to understand the service delivery preferences of homeless youth and understand the outcomes of these choices. Our research questions include: 1. Which approaches to service are chosen by youth? 2. What are the differences and similarities between groups choosing each approach? 3. What are the critical ingredients needed to effectively implement services for homeless youth from the perspectives of youth, families and service providers? Focus groups with staff and family members will occur to assist in understanding the nature of each of service approach, changes that evolve within services, & facilitators and barriers to service delivery. This work will be important in determining which approach is chosen by youth and why. Evaluating the outcomes with each choice will provide valuable information about outcomes for the service options chosen by youth. This assist in better identifying weaknesses in the services offered and inform further development of treatment options that youth will accept.