This research, comprised of 2 studies, extends current knowledge of parent-child communication about drugs. The first study developed a typology of parental strategies used to deter children's substance use. The second study examined relationships among the parental strategies identified in the first study, which included family communication environments and self-reported substance use. Results revealed that parental communication strategies to deter substance use may be employed in different ways by laissez-faire, pluralistic, consensual, and protective families. Of the 7 identified types of strategies, very few actually impacted substance use in the previous 30 days. The only strategy to have a significant effect on the use of all drug types was a "no tolerance rule." Prevention efforts and programs may target parents so as to enhance parental communication competence and offer parents an array of strategies to choose from that might best fit with their family communication environment. (Contains 3 tables and 1 figure.)