Analysis of the data showed that out of the 756 adolescents, 73.2 percent had used alcohol, 54.7 percent had smoked cigarettes, 34.0 percent had smoked marijuana, and 14.2 percent had used at least one hard drug. On this basis a progression scale was formulated beginning with never used substances, used alcohol, used cigarettes, used marijuana, and uses at least one hard drug during the previous six months. The properties of the scale, the coefficient of reproducibility (CR), the minimum marginal reproducibility (MMR), and the coefficient of scaleability (CS) were excellent and indicated that substance use is unidimensional and cumulative. A prospective analysis over two years showed that the temporal sequency of substance uses implied by the Gutman scale represents stages in substance use. Relations between adolescent stage of substance use and adolescent deviant behavior validated the order of substances in the scale. In addition, variables assessing the quality of the relationships in the family were related to level of involvement in substance use and predicted transition to the next developmental stage. This demonstrates the usefulness of this scale in further research on adolescent substance use. 3 tables, 2 notes, and 25 references (Author abstract modified)