U.S. mainland and Puerto Rican nonreferred samples were compared via the Child Behavior Checklist (ages 4 to 16), Teacher's Report Form (ages 6 to 16), and Youth Self-Report (ages 12 to 16). Problem scores were significantly higher in parent and teacher ratings of Puerto Rican than mainland subjects, but were significantly lower in self-ratings by Puerto Rican adolescents. Adolescents in both cultures reported significantly more problems than their parents or teachers did. Most of the significant cross-cultural differences in parent, teacher, and self-ratings of competencies showed more favorable scores for the mainland subjects. High referral rates, a high prevalence of DSM diagnoses, and low scores on the Children's Global Assessment Scale are consistent with the high problem rates reported by Puerto Rican parents and teachers but not with the lower rates reported by adolescents. Different clinical cutoffs may be needed for all assessments in the mainland versus Puerto Rico.