Most modern theories suggest that interpersonal relationships are of central importance in the development of criminal behavior. We tested the parent attachment scales of a new research and clinical measure, the Attachment and Clinical Issues Questionnaire (ACIQ). It is a 29-scale battery assessing attachments to mother, father, partner, and peers, which also includes several related clinical scales. Sixty-one (18-20 years of age) male offenders from a maximum security detention center and 131contrasts completed the ACIQ. ANOVA demonstrated that mother and father attachments displayed different patterns. The attachment scales also predicted the numbers of crimes within the population of juvenile offenders. Thus, the parent attachment scales of the ACIQ showed promise as an instrument to test dynamic systems approaches to developmental models of criminal behavior.