The objectives of this project were to: (a) identify early trajectories of delinquency for both boys and girls at ages 8 (Grade 3), 11 (Grade 6), and 14 (Grade 9) in a longitudinal sample of 842 at-risk youth from a multi-informant perspective (i.e., parents, teachers, self-reported youth ratings), and (b) estimate the costs associated with each delinquency trajectory on utilization of resources in the criminal justice system, remedial education, health care and social services, and social assistance. The results indicated six distinct trajectories of delinquency: two low groups, two desisting groups, an escalator group, and a high delinquency group. There were significantly more females than males in the two<em> low delinquency</em> trajectory groups, <em>p </em>< .05 for both analyses. Furthermore, both the youth from the two <em>desisters</em> trajectory groups (13% of the sample) and from the two most at-risk trajectories (<em>escalators</em> and <em>high delinquency</em>, 5% of the sample) each accounted for approximately 40% of the estimated costs to government. It is interesting to note that 80% of the estimated <em>Criminal Justice</em> costs were due to the <em>high delinquency</em> and <em>escalators</em> trajectory groups. Antisocial or delinquent girls cost society more money than antisocial or delinquent boys in all domains, with the exception of the <em>Social Assistance</em> domain<strong>. </strong>Implications for crime prevention are discussed.