The study's final model detected a long-term, reciprocal link only between the quality of adolescents' relationships with their mothers and internalizing problems. The findings suggest long-term, unidirectional effects on externalizing problems stemming from the quality of adolescents' relationships with their fathers and also with their mothers. The quality of an adolescent's relationship with his/her mother, but not with the father, was associated with both internalizing and externalizing problems over time, confirming the findings of previous studies. Mothers have consistently been found to be more responsive and supportive in responding to adolescents' problem behaviors and emotions, which might explain the importance of this relationship as an inhibiting factor for problematic behaviors and emotions; however, the absence of such a relationship with one's mother can aggravate both internalizing and externalizing problems. Data were collected in two assessments separated by 1 year, in January 1995 and January 1996. Questionnaires were administered in classroom groups of 20-25 students, with sessions conducted later for absent students. Latent variables for externalizing and internalizing problems were measured with the Youth Self-Report, which has shown adequate reliability and validity in assessing a broad range of behavioral and emotional problems experienced by youth ages 11 through 18. The quality of parental relationships was measured with the Inventory of Parent and Peer Attachment. 4 tables, 2 figures, and 67 references