Project Summary/Abstract The Management Core is responsible for leadership and networking; communication and problem resolution; administration; and, implementation of the Recruitment, Engagement, and Retention Center that will identify, recruit and retain all samples for the proposed studies in this U19 application. Two community-based research teams in Los Angeles and New Orleans will screen all intakes at five homeless shelters and gay- identified community based-organizations for 18 months, testing 4500 gay, bisexual and transgender youth (GBTY) and homeless youth (HY) for HIV, sexually transmitted infections (STI), and serious drug use, and obtaining self-reports of mental health, health care utilization, and comorbid conditions. From this initial screening, the 1500 youth at highest risk of acquiring HIV and 220 youth living with HIV will be identified and repeatedly assessed at four month intervals over 24 months. Over this time, 36-90 acutely HIV infected youth will be identified and triaged into potent ARV treatment and a multi-component text, social media, and coaching intervention (Study 1). Interventions with seronegative GBTY and HY and youth living with HIV will also be conducted, with each intervention including both Automated Messaging and Monitoring Interventions and either an eNavigator or Coach. The Management Core will ensure quality assurance and monitor automated indices of performance so that the quality of all activities is to the highest scientific standards and consistent with the values and best interests of the communities and youth participating in the U19 studies. The Management Core will be led by an experienced group of researchers with long histories of productive and cutting-edge findings in adolescent HIV interventions for both seronegative and seropositive youth; experience in the management of large centers, similar to program projects; expertise in acute infections among infants, adolescent medicine, community-based participatory research, STI, and rapid diagnostic tests; and, experience conducting laboratory research across broad distances and executing complex integrated studies on collaborative teams.