A total of 420 Canadian secondary school students participated in the study. Participants completed the Youth Leisure Study Questionnaire developed by Yardley et al. (1996), which is a multivariate instrument that addresses a wide range of adolescent leisure behaviors, school performance measures, and psychological variables. The variables measured pertained to respondents' demographics, sensation-seeking/impulsivity, and substance use. The study used moderated hierarchical multiple regression analyses to examine relationships among predictor, moderating, and outcome variables. Main-effect relationships were consistently found for sensation-seeking/impulsivity with each outcome, but not for gender; however, gender was found to moderate the relationship between sensation-seeking/impulsivity and alcohol use, suggesting that these relationships are more complex than previous literature has suggested. Implications for future research are discussed. 3 tables, 2 figures, and 42 references