Experiences in prenatal life and early childhood that may cause personality disorders or criminal behavior in later life are examined in these proceedings of the Subcommittee on Childhood Experiences as Causes of Criminal Behavior of the Standing Committee on Health, Welfare and Science. This issue, the tenth in a series of 19 hearings dating from November 1977 to July 1978, presents the testimony of Dr. D. R. Offord concerning recent research on antisocial children. Findings suggest that within a relatively poor delinquent population, both school failure and antisocial behavior arise from common or coexisting adverse family influences. It appears that school failure itself is not causally related to antisocial behavior. Improving school performance would not be expected to lessen antisocial behavior. Comparisons among families of the same socioeconomic class, some with delinquent boys and others with nondelinquent boys of the same age, revealed significant differences. Delinquents' families were more likely than comparison families to be headed by single parents and to include parents with a history of mental illness, fathers with a history of criminality, parents with a welfare history and a greater number of children in the house. It is suggested that anything that reduces the parent's resources to care for his or her boy increases the risk of antisocial behavior and delinquency. Three stages of antisocial development are identified. Insufficient parenting between 7 and 10 years and stigmatization as a troublemaker and delinquent at about 11 years are important conditions contributing to continued delinquency. (Author/RH)