This study is part of a larger research project examining family attachment processes. The current study tests a family process model that postulates the mediating role of parent-child attachment and sibling relationship quality in the associations of parent psychopathology or marital adjustment to children's psychological dysfunction. A community sample of 86 families with at least one school-aged (8-12 years) child was recruited from area schools and organizations. Families came to the UNT Family Attachment Lab, where they participated in research tasks, including interviews, self-report instruments, and videotaped interaction tasks. Specific questionnaires used in this study included the Sibling Relationship Questionnaire, the Security Scale, the Behavior Assessment System for Children, the Symptom Assessment-45 Questionnaire, and the Dyadic Adjustment Scale. Using a single indicator for each variable, path analyses tested three paternal models, three maternal models, and three systemic models using different informants' (i.e., father, mother, child) reports of child functioning as the outcome variable. Results of this study highlight the positive relationship between parent marital adjustment and parent-child attachment security, as well as the inverse relationship between maternal psychopathology and mother-child attachment security. In addition, the inverse relationship between parent-child attachment security and child psychological dysfunction was significant across nearly all paternal and maternal models. Particularly noteworthy was the consistent mediating influence of attachment security in the association between marital adjustment and child psychological dysfunction across paternal and maternal models.