This research project examined the individual and combined effectiveness of an HIV prevention workshop and a free condom distribution program in four high schools in Tijuana, Mexico. Adolescents (N = 320) completed baseline measures on sexual practices and theoretical correlates and participated in a two-part study. In Study 1, students were randomly assigned to an HIV prevention workshop or a control condition, with a 3-month follow-up assessment. Results indicate three significant workshop benefits regarding HIV transmission by altering sexual initiation, access to condoms, and traditional beliefs regarding condoms. In Study 2, we set up a condom distribution program at two of the participating schools, and students completed a 6-month follow-up assessment. Results indicate that exposure to the workshop followed by access to the condom distribution program yielded two beneficial results for reducing HIV transmission: moderating sexual initiation and increasing condom acquisition. Access to the condom distribution program alone had no effects on behavioral and psychosocial correlates of HIV transmission. We discuss implications of these results.