Two studies addressed the implications of concordance versus discrepancy of attachment representations in individuals at 2 stages in their marital relationships. Engaged (n = 157) and dating (n = 101) couples participated in a multimethod 6-year longitudinal study of adult attachment. Individuals completed the Adult Attachment Interview (AAI), the Current Relationship Interview (CRI), and various questionnaires and were observed in interactions with partners. On the basis of AAI and CRI classifications, participants were placed in one of four groups: Secure-sub(AAI)/Secure-sub(CRI), Secure-sub(AAI)/lnsecure-sub(CRI), Insecure-sub(AAI)/Secure-sub(CRI), or Insecure-sub(AAI)/Insecure-sub(CRI). Each of the configurations showed a particular pattern of behavior, feelings about relationships and the self, and likelihood of relationship breakup. The findings of the studies address important points about the protective effects of attachment security and have interesting implications for the extension of attachment theory into adulthood.