The study explores the role of working models of attachment in the process of coping with relationship stressors with a focus on long-term adaptation. In a 7-year longitudinal study of 112 participants, stress and coping were assessed during adolescence and emerging adulthood. In addition, working models of attachment were assessed by employing the Adult Attachment Interview (AAI). Individuals classified as having secure working models experienced low stress in relationships with parents, peers, and romantic partners and dealt with relationship stressors more actively by using their social network during adolescence and at the age of 21 years. In contrast, individuals with preoccupied working models experienced high relationship stress, particularly in relationships with parents, and employed less adaptive coping styles over time. Regression analyses revealed that although a preoccupied working model of attachment and withdrawal coping explained variance in symptomatology, relationship stressors were more predictive of poor psychological adaptation.