Review DEPRESSION AND ANXIETY 27 : 556–572 (2010) HOARDING DISORDER: A NEW DIAGNOSIS FOR DSM-V? David Mataix-Cols, Ph.D., 1Ã Randy O. Frost, Ph.D., 2 Alberto Pertusa, M.D., 1 Lee Anna Clark, Ph.D., 3 Sanjaya Saxena, M.D., 4 James F. Leckman, M.D., 5 Dan J. Stein, M.D., 6 Hisato Matsunaga, M.D., 7 and Sabine Wilhelm, Ph.D. 8 This article provides a focused review of the literature on compulsive hoarding and presents a number of options and preliminary recommendations to be considered for DSM-V. In DSM-IV-TR, hoarding is listed as one of the diagnostic criteria for obsessive–compulsive personality disorder (OCPD). According to DSM-IV-TR, when hoarding is extreme, clinicians should consider a diagnosis of obsessive–compulsive disorder (OCD) and may diagnose both OCPD and OCD if the criteria for both are met. However, compulsive hoarding seems to frequently be independent from other neurological and psychiatric disorders, including OCD and OCPD. In this review, we first address whether hoarding should be considered a symptom of OCD and/or a criterion of OCPD. Second, we address whether compulsive hoarding should be classified as a separate disorder in DSM-V, weighing the advantages and disadvantages of doing so. Finally, we discuss where compulsive hoarding should be classified in DSM-V if included as a separate disorder. We conclude that there is sufficient evidence to recommend the creation of a new disorder, provisionally called hoarding disorder. Given the historical link between hoarding and OCD/OCPD, and the conservative approach adopted by DSM-V, it may make sense to provisionally list it as an obsessive–compulsive spectrum disorder. An alternative to our recommendation would be to include it in an Appendix of Criteria Sets Provided for Further Study. The creation of a new diagnosis in DSM-V would likely increase public awareness, improve identification of cases, and stimulate both research and the development of specific treatments for hoarding disorder. Depression and Anxiety 27:556–572, 2010. r r 2010 Wiley-Liss, Inc. Key words: hoarding; obsessive–compulsive disorder; obsessive–compulsive person- ality disorder; Anankastic personality disorder; DSM-V; classification; nosology Published online 24 March 2010 in Wiley InterScience (www. interscience.wiley.com). DOI 10.1002/da.20693 Received for publication 3 November 2009; Revised 22 February 2010; Accepted 23 February 2010 Ã Correspondence to: David Mataix-Cols, King’s College London, PO 69, Institute of Psychiatry, De Crespigny Park, London SE5 8AF, United Kingdom. E-mail: david.mataix-cols@kcl.ac.uk This article is being co-published by Depression and Anxiety and the American Psychiatric Association. The authors report they have no financial relationships within the past 3 years to disclose. 1 King’s College London, Institute of Psychiatry, London, United Kingdom 2 Department of Psychology, Smith College, Northampton, Massachusetts 3 Department of Psychology, University of Iowa, Iowa City, Indiana 4 Obsessive-Compulsive Disorders Program, University of California, San Diego, California 5 Child Study Center, Yale University School of Medicine, New Haven, Connecticut 6 Department of Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa 7 Department of Neuropsychiatry, Osaka City University Graduate School of Medicine, Osaka, Japan 8 Obsessive–Compulsive Disorder Clinic, Department of Psychia- try, Massachusetts General Hospital, Boston, Massachusetts r r 2010 Wiley-Liss, Inc.