Evidence is provided indicating that the measures of self-control theory (i.e. low self-control, opportunity, and delinquency) and the causal model using these measures were different for males and females. The results suggest that males have lower self-control, greater opportunity for delinquency, and commit more delinquency than females. Gottfredson and Hirschi’s version of self-control theory assumes that humans are rational beings and that when they are the products of poor or ineffective parenting, they may have low self-control. When matching low self-control with opportunity, the propensity for criminal and delinquent behavior increases. However, there are unresolved issues when examining the role of sex in the theory. The purpose of this study is to contribute to the literature by examining the distribution differences and causal model from self-control theory, taking into consideration the role of opportunity. Taking into account opportunity in the context of sex differences in self-control theory provides a direct test of two of Gottfredson and Hirschi’s arguments. The study provides criminologists with an understanding about hypotheses from Gottfredson and Hirschi’s theory. Table, figure, appendixes A-B, notes, and references