Those who begin offending before the teenage years tend to commit large numbers of offenses over long periods of time and at high rates. The onset of offending is important because it provides the first opportunity for intervention by the court system or social welfare system. This report considers possible intervention techniques which might prevent onset or continuation after onset. It is necessary to investigate individual sequences of onsets of different kinds of offenses and deviant behaviors and to determine the probability of one behavior following another as well as the time interval between onsets. It is important to establish the ages at which different types of offenses are committed for the first time and to plot age specific hazard curves. Although little is known about the predictors of age onset, one study showed the best predictors to be rarely spending leisure time with the father, troublesome behavior, authoritarian parents, psychomotor impulsivity, low family income, low non-verbal intelligence, and poor parental child-rearing behavior. It is necessary to study the link between delinquent behavior in elementary school and later criminal careers, but the main concern should be how to interpret the continuity from child conduct problems to juvenile delinquency. It is necessary also for preventive interventions to address the risk factors which are important precursors of antisocial and delinquent behavior. Four particularly hopeful intervention strategies identified by the authors are promoting individual competence, improving poor parenting, fostering prosocial peer influences, helping children resist antisocial peer influences, and improving academic performance. Questions raised by the study would be best addressed in longitudinal studies following children between the age of six and twelve to learn more about the onset of offending and successful intervention targeted with wide ranging benefits in reduction of a variety of troubling social problems such as drug and alcohol abuse, dangerous driving, abuse of spouses and children, and some types of psychiatric illnesses. 1 table, 222 references, 5 appendixes.