Hoarding disorder (HD) is a chronic and progressive condition that causes people to accumulate more objects than their homes can accommodate. It affects as many as 14 million people in the United States, with one estimate suggesting it impacts about two percent of the population. Individuals with hoarding disorder have trouble making decisions about when to throw things away, leading to debilitating clutter as possessions pile up. Hoarding disorder was first recognized as a separate condition by the Diagnostic and Statistical Manual of Mental Disorders (DSM) in 2013. This book includes quotes and statements from experts and stakeholders about hoarding disorder and hoarding behavior, as well as the impact of hoarding behavior on communities.