Subjects included two samples of 18- to 24-year-olds from a low income, minority neighborhood in New York City: a probabilistically selected household sample; and a targeted sample of users of cocaine, heroin, crack, or injected drugs. Recalled norms at age 15 were shown to be significant predictors of current drug use, both in general and for specific drugs. Norms varied by drug, heroin, crack, and injected drugs. A strong relationship was found between recalled norms and current use both for individual drugs and for a hierarchically defined level of drug use. This relationship remained significant after controlling for sociodemographics and parental and sibling drug use. Intervention programs for young teens that influence peer selection and norms of groups of adolescents should be developed and tested. Two ways in which programs might affect a client’s peer norms are changing the peers the client associates with, and changing the norms of the client’s peers. Efforts can be made to increase the likelihood that individuals choose peers who are more likely to object to drug use and less likely to encourage it, or efforts can be made to increase the number of adolescents who object to and do not encourage drug use. Research is needed on the social, economic, political, and other determinants of norms in their neighborhood contexts. 1 figure, 3 tables, 2 notes, and 53 references.