This study tested the generality of Jessor and Jessor's (1977) problem behavior theory, which states that a variety of problem behaviors constitute a behavioral syndrome in normal adolescents. Relationships among 5 adolescent problem behaviors (cigarette use, alcohol use, marijuana use, delinquency, and sexual intercourse) were examined in 7th-grade boys (n = 556) and girls (n = 715), and 9th-grade boys (n = 481) and girls (n = 485) in an urban school system in which the majority of students were African American and from low-income families. Measures of problem behavior frequency were positively correlated with each other and negatively correlated with several measures of conventional behavior. Confirmatory factor analyses replicated findings of previous studies that a single common factor underlies adolescent problem behaviors.