This study examined the timing of several events marking the transition from adolescence to young adulthood and their correlation with the age at first sexual intercourse. The model included parental disruption, dropping out of school, working, drug use, and dating. Socioeconomic status, gender, and race were included as control variables. Data are taken from the National Survey of Children, a longitudinal study of children ages 7-11 in 1976 who were reinterviewed in 1981 and 1986. Factors associated with first intercourse include age, tobacco use, marijuana use, dating, and parental divorce during the child's adolescent years. Age interacts with dating, working, and the use of illegal substances, and race interacts with dating and dropping out of school in their influence on first intercourse. Other transitions, such as alcohol use, parental divorce before adolescence, and parental marriage, had little influence on first sexual intercourse. Events such as dating appear to increase the risk of first intercourse, while the use of drugs may reflect a set of behaviors that occur simultaneously with sexual initiation. The correlated transitions identify a group of adolescents at risk for early sexual activity.