AIMS: The purpose of this study was to examine parental monitoring practices and religious involvement (protective factors) and substance use among Mexican American and Non-Latino adolescents in the Southwest of the United States. FRAMEWORK: We also relied on social control theories to guide our investigation of why adolescents may choose not to use drugs. PARTICIPANTS: The sample was N=1087 adolescents, the age ranged from 13 to 15 years, and the gender distribution was approximately equal. There were 71% Mexican Americans and 29% non-Latinos in the sample. METHODS: a number of measures were used including recent substance use, religiosity, religious affiliation, parental monitoring, parental permissiveness, parental norms, and acculturation. Linear regressions were used to examine the relationship between the variables of interest and the outcomes. RESULTS: Although the effect sizes of the significant relationships were modest, the findings are of interest because they reinforce the importance of the role of parents in the lives of their adolescents and supports previous studies that find that parents have great influence on children's behaviors including substance use. The results suggest that acculturating adolescents benefit from having clear rules from their parents concerning substance use, and from believing that there is some kind of consequence attached to their behavior. Parental monitoring, by itself, did not explain lower levels of drug use among these adolescents; but it was a predictor of adolescent strong anti-drug personal norms. This study is useful to social workers and other professionals working with parents and adolescents as it provides concrete evidence of possible parents pathway of influence on their children's health status.