Background: School-based human immunodeficiency virus (HIV)/sexually transmitted infection (STI), and pregnancy prevention programs often focus on consistent and correct condom use. Research on adolescents' experience using condoms, including condom slippage/breakage, is limited. This exploratory study examines proper condom use and the occurrence of condom slippage/breakage among alternative school youth. Methods: Data are from an HIV/STI prevention trial for youth in continuation school settings (N = 776). Analyses included separate hierarchical logistic regression analyses to explore the relationship between potential correlates and each outcome variable. Results: Students' use of steps for proper condom use varied--73.8% put on the condom before sexual contact, 71.1% squeezed air from the tip, and 92.0% unrolled the condom fully. Notably, 28.5% reported condom slippage/breakage. Results from the regression analyses showed that 4 sets of variables (demographic, substance use, sexual risk behaviors, and condom psychosocial factors) were associated with putting on a condom before sexual contact; none of the variable sets were associated with the other 2 condom steps measured. For slippage/breakage, the demographic and sexual risk behaviors were significant correlates; steps for proper condom use approached statistical significance (p = 0.058). Conclusions: This study extends the limited research on how adolescents use condoms, and highlights important targets for prevention interventions. (Contains 3 tables.)