ENBackground: Adjustment disorder (AjD) is one of the most used mental disorder diagnoses among mental health professionals. Important revisions of the AjD definition in the 11th edition of the International Classification of Diseases (ICD-11) are proposed. AjD is included in a chapter of disorders specifically associated with stress in ICD-11. Objective: This paper aims to review recent developments in ICD-11 AjD research, and to discuss the available ICD-11 AjD diagnosis validation studies, AjD measures, treatment studies, and outline the future perspectives for AjD research and clinical practice. Methods: In total, 10 empirical studies of AjD ICD-11 were identified and included in this review. We searched for studies in Embase, PubMed, PsycINFO, Scopus, PILOTS, SocINDEX, and via additional search by contacting authors of published empirical studies and reference screening. Results: Review of the studies revealed a lack of validation studies of the ICD-11 AjD symptom structure. AjD validation study findings are ambiguous, and there is still little support for the proposed two symptom structure of AjD for the ICD-11. A self-report AjD measure ‘Adjustment Disorder New Module’ (ADNM) based on the ICD-11 definition has been developed and used in all 10 reviewed studies. Two self-help interventions have been developed for the ICD-11 AjD, and findings from these studies indicate that self-help lowintensity cognitive-behavioural interventions, delivered via bibliography or internet-based, might be effective treatment of AjD. Conclusions: The AjD definition in ICD-11 with a description of a new symptom profile facilitates AjD measurement and AjD-focused treatment developments. More studies and insights from clinical practice are needed to move the field of AjD research and practice forward. Keywords: Adjustment disorder; ICD-11; review; validation; assessment; treatment. [From the publication]