Abstract
Open-ended questions on antecedents of problem substance use were administered to 195 men and women in treatment. Examination of responses revealed distinct differences between precursors of problems, depending on which of a possible 11 classes of substance was being discussed. A model in flow-chart form encapsulates the common elements generally shared by this population, and it highlights the central role of availability in the development of problems. The model also suggests a possible explanation for recidivism among misusers who have undergone treatment.