In 1995, the first designated treatment program for adolescent drug abusers in England was established in Stoke-on-Trent. In 1998, a similar program was developed in Newcastle-upon-Tyne. The current study interviewed 103 adolescent drug users (95-percent response rate) who were attending these 2 programs. Forty-six of their parents (70-percent response rate) were also interviewed. The interviews were conducted between June 2001 and June 2002. An indicator of the level of problematic drug use (LPDU) was developed. This indicator focuses on frequency of use, types of drugs used, reasons for drug use, route of administration, and current spending on drugs. The study used Structural Equation Modeling (SEM) to develop path diagrams. The study used two exploratory models, with the first model focusing on the precursors of the level of problematic drug use and the second model analyzing the consequences of the level of problematic drug use. The study found that the respondents had been using drugs for an average of 3.6 years. The analysis identified the relative hierarchy of 10 factors that predicted increased LPDU within the sample. In hierarchical order, these factors were perceived lack of parental discipline; respondent's friends using drugs; age at interview; history of running away from home; parental lack of concern about smoking and alcohol problems; additional deviant behavior; perception of poor local amenities; age at initiation into substance use; poor school attendance; and not living in a household with adults. The impact of material deprivation and social exclusion on the level of problematic drug use was indirect. The data suggest a number of promising options, including parenting-skills training, cognitive behavioral therapy, Communities that Care, and multisystemic therapy. Further, adolescent drug users who are seeking help should be assessed regarding their motivation to change their behavior, since this may increase the probability of a positive outcome. Cognitive behavior therapy helps patients recognize why they are using drugs and determine what they must do to either avoid or cope with whatever triggers their use. 14 figures, 13 tables, 74 references, and appended main variables in the questionnaire, school indicators, parental data, a comparison of drug use between the two program samples, and potential measures of fiscal exclusion