The authors present analyses specific to drinking alcohol, getting drunk, tobacco use, use of marijuana or hashish, and use of harder drugs to determine if factors common to a sensation- seeking perspective help explain both the prevalence and frequency of substance use among adolescents. Findings provide strong support for considering sensation-seeking variables such as thrill-seeking, immediate gratification, and impulsivity to help explain self-reported substance use. Results show that for each of the five substance delinquencies examined, sensation- seeking factors generate statistically significant influences. Results point toward intrinsic rewards that initially promote and subsequently reinforce substance use; these perceived rewards include fun, thrills, the physiological "high" generated by drug or alcohol use, and the excitement of doing something illegal. The relevance of a sensation-seeking approach to social learning theory is explored. 4 tables and 34 references