ABSTRACT
Qualitative data from 923 adolescents treated in outpatient and residential settings were used to create taxonomies of their reasons for starting, continuing, and quitting use of drugs and alcohol. Three raters independently categorized reasons by dominant theme. The final sets of taxonomies were defined within several iterations and the raters' use of the categories showed strong inter-rater agreement. Frequencies of reasons were examined overall and by level of care. Adolescents reported initiating use due largely to experimentation and peer influence, continuing use due to liking the effects and assistance with coping, and quitting due to negative appraisals and effects. Reasons differed by level of care.