A total of 103 children, 6-12 years-old, were evaluated in either the child psychiatry outpatient clinic or the child psychiatry inpatient unit of Bronx Municipal Hospital Center, Bronx, N.Y. All children admitted to the inpatient service from December 1976 to February 1979 were included in the study, as were all children evaluated in the outpatient clinic from March 1978 to February 1979. The children were from a low to low-middle socioeconomic background. They were evaluated using the standard clinic and inpatient assessment procedures, which included individual child and family interviews as well as neurological and IQ testing. In addition, a set of research scales was used to collect data on each child. A scale was constructed to represent a spectrum of assaultive behavior. A child was rated assaultive if he/she demonstrated any type of assaultive ideas, threats, attempts, or homicide during the 6 months preceding the evaluations. No racial or ethnic differences were found in assaultive children, but boys were significantly more assaultive than girls and used firesetting and hitting with objects more often. Inpatients were significantly more assaultive than outpatients, while children with conduct disorders, specific developmental disorders, and mental retardation were more assaultive than those with neurotic disorders. Multiple regression analysis showed that the child's past aggressive behavior, absence of anxiety and depression, and parental assaultive behavior were the best predictors of assaultive behavior. Appended are definitions of classification on a scale measuring assaultive behavior in children. Tabular data and 31 references are provided.