Maladaptive relationship patterns that are learned in early attachment relationships can be replicated with others in adulthood in predictable patterns referred to as “copy process” in Interpersonal Reconstructive Therapy (IRT, Benjamin, 2003/2006; 2018). The underlying attachment-based motivations to repeat old patterns can provide barriers to response to standard treatments while also holding the keys to change with even difficult or “stuck” cases. This presentation will provide an overview of IRT principles, including review of empirical evidence supporting their use. Case illustrations will emphasize use of an interpersonal case formulation to tailor treatment for severe and chronic problems involving diagnostic comorbidity and personality pathology. Ultimately, IRT seeks to help patients become aware of copied interpersonal and intrapsychic patterns, and the role they play in maintaining connection with internalized attachment figures. From there, the goal is to help a patient differentiate from the “family in the head” and pursue healthy behaviors and self-concepts.