This study confirms Gottfredson and Hirschi's theory on the direct link between a person's ability to control his/her impulses and behavior and delinquency. However, this study found that parental behavior toward a child influenced that child's risk for delinquency in more ways than only through its impact on the child's self-control; for example, authoritative parenting as well as improvements in authoritative parenting significantly lowered involvement in delinquency, even after controlling for self-control. Further, the assumption of stability in self-control after age 10 was not supported. The findings thus suggest that Gottfredson and Hirschi's focus on the stability of parenting practices and the resulting levels of self-control in children must be modified to encompass changes in a child's self-control as a result of changes in parenting styles and the nature of the child's social interactions outside the home. Improvements in authoritative parenting and increases in prosocial peers and attachment to teachers were associated with decreases in low self-control. The influence of social relationships on self-control at the second wave occurred despite controls for earlier parenting and self-control and explained a substantial portion of the variance. This study used two waves of data from the Family and Community Health Study, a longitudinal, multisite investigation of neighborhood and family effects on health and development. The study sample consisted of 259 African-American families living in Georgia (n=115) and Iowa (n=144). 5 tables, 97 references, and appended measures of low self-control and authoritative parenting