Adolescent Safer Sex Social Network Intervention

Inclusion Criteria: Index Participant Inclusion Criteria * Self-identifies as all or part "Latino" * Age is between 16 years and 0 days and 19 years and 364 days at the time of study enrollment * In the past 3 months, reports engaging in any type of heterosexual sex (vaginal, oral or anal) with an opposite-sex partner * In the past 3 months, reports any of the following: * alcohol use at least once; * marijuana use at least once; * having sex while drunk or high. * Must understand spoken and written English sufficiently to provide consent/assent and be interviewed and attend intervention workshops delivered in English * Must live in the Boston or Tampa area, and plan to be available for study appointments (vacation allowed if not interfering with the planned intervention or follow up dates) Network Participant Inclusion Criteria * Age is between 16 years and 0 days to 19 years and 364 days at the time of study enrollment * In the past 3 months, reports engaging in any type of heterosexual sex (vaginal, oral or anal) with an opposite-sex partner * Must understand spoken and written English sufficiently to provide consent/assent and be interviewed and attend intervention workshops delivered in English * Must live in the Boston or Tampa area, and plan to be available for study appointments (vacation allowed if not interfering with the planned intervention or follow up dates) * Must be reported by an index as a friend who: * has been known for at least 6 months; *…