This article focuses on the relationship between crime and social disadvantages by applying Situational Action Theory (Wikström 2006, 2009; Wikström et al., 2012) to explain the delinquent behaviour of adolescents. According to Situational Action Theory, criminal acts are the result of a perception-choice process that is guided by the interaction of a person’s crime propensity and the criminogenic conditions of the environment. Social disadvantages are not causes of criminal behaviour but rather causes of the causes. Social disadvantages affect the emergence of crime propensity and criminogenic exposure of individuals. This relationship between crime and disadvantages in the context of Situational Action Theory will be empirically tested by applying structural equation modelling and testing for indirect effects of several structural heterogeneities. The results show that the relationship between heterogeneity features and delinquency for the most part is mediated by the theoretical assumptions of SAT.