In collaboration with the Lyon Martin Health Services (LMHS), the Trans Wellness Service Integration (TWSI) project as part of the Health Intervention Projects for Underserved Populations (HIPUP), Public Health Institute (PHI) aims to implement HIV, substance abuse, and mental health prevention and treatment programs for gender non-binary people (GNBP) in Alameda and San Francisco Counties, California. TWSI interventions will be based on EBPs: Motivational Enhancement Intervention (MEI) and Trauma-Focused Cognitive Behavioral Therapy (TF-CBT). Through direct and online outreach, we will recruit high risk GNBP adults including transwomen, transmen, and gender non-binary people and provide intake assessment, HIV/Hep testing, and referrals for prevention (e.g., PrEP and vaccination) and treatment (ART) at LMHS. Peer Counselors will work with clients to reduce HIV risk and substance use behaviors and promote mental health and access to GNBP support services [e.g., Stable Housing and Employment (SHE)] based on MEI and Peer Support Groups. After completing MEI sessions, clients who do not show improvement will be referred to Professional Counseling based on MEI and/or TF-CBT. We will provide comprehensive referral and navigation services for HIV/Hep treatment and other health and social services that are sensitive to GNBP. Also, we will disseminate project activities and findings through our project website and SNS to increase awareness and knowledge for HIV and substance abuse prevention and treatment and mental health promotion for GNBP. We will attain the following measurable objectives: 1) Develop and complete 12 Memorandum of Agreements (MOAs) with collaborating service agencies; 2) Establish the Community Advisory Board (CAB) and meet quarterly; 3) Conduct community- and online outreach and make 5,250 contacts with high-risk GNBP in Alameda and San Francisco counties; 4) Screen eligibility for 3,150 GNBP and provide referrals for prevention and treatment; 5) Enroll 420 GNBP into TWSI, conduct intake assessment, and HIV and Hep testing; 6) Provide all 420 clients with Peer Counseling/Case Management; 7) Enroll 42 newly diagnosed HIV clients or those dropped out into HIV primary care; 8) Enroll 140 clients into PrEP; 9) Screen for substance use and mental health disorders for 210 clients; 10) Enroll 106 clients into Professional Counseling; 11) 110 clients enroll in Peer Support Groups; 12) 378 clients complete Peer/Professional Counseling and the exit interview; 13) 336 clients (80%) complete the 6-month follow-up assessment; 14) Conduct 48 process evaluation; 15) Conduct 4 outcome evaluation; 16) 210 clients significantly reduce HIV risk and/or substance use behaviors and/or mental health problems at 6-month follow-up compared with the intake assessment; 17) Disseminate project findings and experience through 8 community forums and online (2,250 clicks on our project website or positing on SNS). TWST is an ideal expansion and enhancement of our current services for GNBP who are struggling with HIV/AIDS, substance use, and mental health problems and a lack of coordination of these vital prevention and treatment services.