This rejoinder proposes how the five trait domain qualifiers of the ICD-11 personality disorder classification may capture personality dynamics, while also being feasible in various clinical settings. It is highlighted that the simple coding of one to five trait qualifiers may serve as a basic step in the process that leads to a clinical management plan; for clinicians with more resources, a second step may involve taking advantage of the 25 detailed DSM-5 AMPD subfacets for a more fine-grained case-formulation and treatment planning. Moreover, the ICD-11 trait domain qualifiers seem to take personality dynamics into account, which is exemplified by how different trait domain combinations may involve different situational and motivational trait domain expressions that demand different treatment implications.

The DSM-5 Alternative Model of Personality Disorders (AMPD) and the ICD-11 Classification of Personality Disorders allow clinicians to describe trait domains that contribute to the unique expression of personality dysfunction. Both diagnostic systems deliniate trait domain features of negative affectivity, detachment, antagonism/dissociality, disinhibition, and anankastia/compulsivity, which may inform clinicians about how to manage treatment. This chapter specifically describes how the DSM-5 and ICD-11 trait domains may be useful for establishing a favorable treatment alliance, doing therapeutic assessment, increasing the patient’s self-knowledge, providing psychoeducation, planning realistic treatment goals, and matching therapy to the patient’s personality. A key message of this chapter is that practitioners should not treat traits per se but the maladaptive expressions of traits.

Collaborative/therapeutic assessment (C/TA) adds value to psychological assessment by enhancing the therapeutic effects assessment can have. This chapter tracks the influences and research that have guided the evolution of assessment into C/TA and therapeutic assessment (TA), which is a semi-structured C/TA designed to maximize therapeutic effects. It describes the steps and techniques of TA, including developing the client’s questions for an assessment to address, extended inquiry, assessment intervention sessions, and summary discussion sessions. It then explores the empirical foundation that supports the efficacy of C/TA and TA. The added value that TA offers is outlined, including its contribution to working with clients struggling with personality disorders and issues involving epistemic hypervigilance. Finally, discussion of future research that could further TA as an effective consultation technique and as a stand-alone therapeutic intervention itself is considered.