To identify the differences and similarities in sexual and contraceptive knowledge, attitudes, and behavior among Latino male adolescent students living in California and Lima. Self-administered, anonymous surveys were completed by Latino male students aged 12-19 participating in California, and by male adolescent students in four high schools in Lima. Both surveys contained similar questions allowing for comparisons regarding sexual activity and contraceptive behavior. The mean age of male students were 16 and 15 years, respectively. More California males reported having engaged in sexual intercourse (69% vs 43%. The sexual debut was 13 years in both samples. More students in California were aware of their risk of pregnancy at first sexual intercourse than in Lima (82% vs 50%). One-third of the California males reported communicating with their partner about sex and contraception to be "easy" as compared to 53% of males in Lima. More students in California reported knowing a place to obtain contraceptives if they need them (85% vs 63%), having ever gotten someone pregnant (29% vs 7%), and having fathered a child (67% vs 16%).