A non-separation diagnostic framework for assessing canine attachment structure.

Conventional diagnostic approaches to canine attachment and separation-related behaviors rely primarily on behavioral outcomes observed during induced separation from the caregiver. While widely adopted, separation-based assessments may conflate superficially similar behaviors that arise from fundamentally different caregiver-dog relational structures (e.g., secure regulation vs. avoidant disengagement vs. ambivalent hyper-proximity), thereby raising ethical, conceptual, and interpretive limitations. This study proposes a non-separation diagnostic framework for assessing canine attachment structure through everyday interactional observation, without inducing caregiver absence. Drawing on long-term naturalistic observation of dogs living in stable human environments and structured non-separation observation of representative cases, attachment-related organization was consistently observed as identifiable prior to any separation event. Diagnostic assessment focused on exploration-return organization (i.e., exploratory expansion followed by repeated voluntary returns to caregiver proximity as a regulatory anchor), distance regulation patterns, emotional stabilization following return, and caregiver emotional responsiveness. Across observed cases, attachment structures were consistently observable under non-separation conditions. Behaviors later expressed during separation were found to reflect amplification of pre-existing relational organization rather than responses generated by separation itself. Two procedural cases are presented to illustrate the diagnostic necessity of this framework. In the first, a presentation superficially resembling secure attachment was procedurally excluded due to absence of exploration and failure of emotional regulation. In the second, overt separation-related distress was observed, yet secure attachment organization was supported through intact non-separation structure. Together, these cases demonstrate that neither proximity nor separation behavior alone can serve as diagnostic criteria. The proposed framework repositions separation as an expressive context rather than a causal diagnostic trigger and establishes non-separation observation as the primary context for attachment classification. This approach offers a conceptually coherent and ethically grounded diagnostic alternative and provides a methodological foundation for subsequent applied and clinical studies of canine attachment.