While widespread survey research has been conducted on the substance use patterns of young people, these surveys are generally school-based and thus fail to incorporate information on substance use among young people excluded from school. Moreover, recent evidence has suggested that adolescent substance use is related to school status. The current study was part of the Belfast Youth Development Study (BYDS) on the onset and development of adolescent substance abuse. Participants were 48 young people aged 13 and 14 years who were excluded from school in the Greater Belfast area and were attending alternative education provision. Participants completed questionnaires probing drug use patterns, delinquency, school factors, criminal justice system contact, leisure activities, and family issues. Their results were compared to the data obtained from 4,438 young people attending 43 schools in Belfast. Results indicated that the excluded youth were already engaging in high-risk behaviors that could lead to problem drug use, especially when compared to their counterparts within the mainstream educational system. The findings underscore the need for targeted drug prevention strategies that meet the needs of high-risk youth. Future research should focus on developing a full profile of the life experiences of high-risk young people throughout their adolescence. Tables, references