WHO International Classification of Diseases 11th Revision
Hoarding disorder is characterised by accumulation of possessions due to excessive acquisition of or difficulty discarding possessions, regardless of their actual value. Excessive acquisition is characterized by repetitive urges or behaviours related to amassing or buying items. Difficulty discarding possessions is characterized by a perceived need to save items and distress associated with discarding them. Accumulation of possessions results in living spaces becoming cluttered to the point that their use or safety is compromised. The symptoms result in significant distress or significant impairment in personal, family, social, educational, occupational or other important areas of functioning.