This prospective study examined the role of personal and family factors during early adolescence in forecasting sexual activity, a behavior of major concern in the 1990s. Also, the correlates of late adolescent/young adult sexual activity, including delinquency and psychological adjustment, were examined. One hundred and thirty individuals were assessed at two points in time, during adolescence and six years later during late adolescence/young adulthood. Results supported the existing literature regarding the sexual activity of today's youth, indicating that the majority of both males and females are sexually active by late adolescence/young adulthood (age 18-21), and that the average adolescent/young adult has had multiple partners (females: 2-3; males: 3-4). For both males and females, adolescent sexual activity was correlated with problem behavior (i.e., delinquency), but rarely with prosocial behavior, during late adolescence/young adulthood. For females, but not for males, parental divorce during early adolescence was associated with earlier onset and greater frequency of sexual activity, as well as more sexual partners.