Opening Doors Through Services and Supports for Homeless Individuals with SMI or CODs (Opening Doors) will support the development and expansion of local implementation of an infrastructure that integrates behavioral health treatment and recovery support services for individuals with serious mental illnesses (SMI) and co-occurring substance use disorders (hereafter referred to as CODs) who are experiencing homelessness, with a priority population of emerging adults aged 18-24 years old. Opening Doors will implement three evidence based practices: Housing First, Seeking Safety and Integrated Dual Disorder Treatment. The program will screen 2,400 homeless individuals and enroll 600 individuals with SMI and CODs in services (unduplicated, 300 per site) over the life of the grant (FY1=100, FY2=130, FY3=140 FY4=130, and FY5=100). Given that the prevalence of CODs among homeless populations ranges between 20% and 50%, we anticipate 35% (N = 210) of enrollees will have a COD. Our goals are the following to: (1) increase the capacity to provide outreach and other engagement strategies to identify homeless individuals with SMI or CODs, with a focus on youth 18-24 years old; (2) increase the capacity to assist with identifying sustainable permanent housing for homeless individuals with SMI or CODs; (3) increase the capacity to provide evidence based, trauma focused services to homeless individuals with SMI or CODs that address symptoms and behaviors associated with homelessness and housing retention; (4) increase the capacity to screen and refer individuals with SMI or CODs experiencing homeless for primary health indicators; (5) increase the capacity to EBPs to homeless individuals with SMI or CODs to address symptoms and behaviors associated with homeless-ness & housing retention; (6) increase the capacity to collaborate across agencies to ensure coordinated care and share lessons learned with the larger statewide Housing Leadership Group; and (7) demonstrate improved outcomes among enrolled individuals.