The Child Behavior Checklist's applicability to a Hispanic sample was assessed by an examination of the instrument's internal consistency and concurrent validity. The CBCL and TRF were administered to a community sample representative of children of Puerto Rico aged 4 to 16. Cronbach's alpha was used to assess the internal consistency of empirically derived scales. The relation of CBCL and TRF scores to clinical diagnosis, adaptive functioning, and need for services served as indicators of the concurrent validity of the instrument's Spanish version. The results indicate that the total behavior problem scores on the instruments are good continuous measures of maladjustment for children in Puerto Rico. A child with high values on the scales has a high probability of being classified as a case by a psychiatrist. High levels of internal consistency were found in most subscales. Only scales comprising low prevalence problems showed poor internal consistency.