OBJECTIVE: The objective of this study was to examine the associations among gender-differentiated motivational orientations (integrative and instrumental), acculturation success, and risky behaviours (illicit substance use and gambling behaviour) among Iranian youth who have immigrated to Toronto. DESIGN: Given the exploratory nature of the proposed research, a cross-sectional research design was used. SUBJECTS: A combination of purposive-proportional quota sampling and snowball sampling methods were employed. The sample for this research was comprised of 308 participants (M=155, F=153) who 1) were born in Iran, 2) had recently immigrated to Canada from Iran 2-8 years ago, and 3) were currently attending high school, enrolled in Grade 9, 10, 11, or 12 (ages 15 to 18) in Toronto. RESULTS: The results of the current study confirm 1) the findings in the existing literature that adherence to an instrumental motivational orientation is positively correlated with risktaking behaviours; 2) confirm some of the existing literature findings, which suggest that lower levels of acculturation are negatively associated with problem behaviours; 3) show that males possess an instrumental motivational orientation significantly more than females, and that females possess an integrative motivational orientation significantly more than males; 4) indicate that male participants show significantly lower levels of acculturation while female participants demonstrate higher level of acculturation, which confirms that acculturation is significantly determined by gender; and 5) partially support some of the claims in the literature; for example, it found males are more at risk for illicit drugs, while females to be more at risk for alcohol consumption. DISCUSSION The current study is among the first to examine the interrelationships among illicit substance use and gambling behaviour, acculturation success/stress, and motivational orientation among Iranian adolescent immigrants. To understand the predictors of success or failure among adolescent youth, replication of the current study is necessary. / Psychology / D. Litt. et Phil. (Psychology)