Compulsive hoarding (or pathological collecting) is a pattern of behavior that is characterized by the excessive acquisition of and inability or unwillingness to discard large quantities of objects that would seemingly qualify as useless or without value. Compulsive hoarding behavior has been associated with health risks, impaired functioning, economic burden, and adverse effects on friends and family members. When clinically significant enough to impair functioning, hoarding can prevent typical uses of space so as to limit activities such as cooking, cleaning, moving through the house, and sleeping. It can also be dangerous if it puts the individual or others at risk for fire, falling, poor sanitation, and other health concerns.
Contributions by Sk8tr49, Ocdgader, and Habanero-tan.