Attachment theory suggests, first, that patterns of dyadic behavior cohere across salient relationships and, second, that such linkages are mediated by working models, defined as cognitive/emotional representations of relationships abstracted from dyadic experience. In this longitudinal study, adolescents' (age 19) Adult Attachment Interview (AAI) coherence ratings and classifications (e.g. working model proxies) were related prospectively to their observed dyadic behaviors with romantic partners in young adulthood (age 20-21). Results demonstrated significant associations between adolescents' representations of their relationships with parents and the later quality of their interactions with romantic partners. Next, a model was tested whereby participants' working models, as inferred from the AAI, mediate the across-time correlation between a subset of observationallv assessed parent-child dyadic behaviors (age 13) and the romantic relationship behaviors of these participants eight years later in young adulthood (age 20-21). Results of mediational analyses were consistent with the fundamental tenet of the organizational-developmental model that salient parent-child experiences are internalized and carried forward into adult relationships.