The authors examined the relation between dimensions of attachment and internalizing and externalizing problems in 15- to 16-year-old adolescents (n = 62) who completed the Attachment Style Questionnaire (ASQ; J. Feeney, P. Noller, & M. Hanrahan, 1994) and the Youth Self-Report (YSR; T. M. Achenbach, 1991). In total, the ASQ dimensions accounted for 48% of the variance in scores on the broad YSR internalizing problem scale. Three ASQ dimensions (confidence, discomfort with closeness, preoccupation with relationships) accounted for unique variance. Girls exhibited higher problem scores than did boys even when the authors considered ASQ scores. The authors observed comparable results for the anxious/depressed subscales. The confidence, discomfort, and preoccupation dimensions predicted scores on the withdrawn subscale. The authors observed weak relations or no relations between results on the ASQ and the externalizing problems scale. In conclusion, dimensions of attachment are powerful predictors of internalizing problems in adolescents. The authors discussed the potential cause and effect relationship between attachment variables and self-reported problems. (Contains 3 tables and 2 notes.)