This study examines the effects on adolescent offending of lifestyle risk and the individual propensity to offend. It is assumed that lifestyle risk will have a more important effect on offending for those individuals with high levels of individual propensity, whereas for individuals with low levels of individual propensity it is assumed that a risky lifestyle will not, or will only marginally, influence their involvement in offending. The data are drawn from two different samples of young adolescents in Antwerp, Belgium (N = 2,486), and Halmstad, Sweden (N = 1,003). The data provide strong support for the hypothesis that the effect of lifestyle risk is dependent on the strength or weakness of individual propensity, indicating that lifestyle risk has a stronger effect on delinquency for individuals with a high propensity to offend. The similarity of the results across two independent samples suggests the findings are stable. (Contains 5 notes, 2 tables, and 1 figure.)