Hoarding disorder, classified as one of the obsessive-compulsive and related disorders in the DSM-5, presents particular challenges in therapeutic work, including treatment ambivalence and lack of insight of those affected. This evidence-based guide written by leading experts presents the latest knowledge on assessment and treatment of hoarding disorder. The reader gains a thorough grounding in the treatment of choice for hoarding a specific form of CBT interweaved with psychoeducational, motivational, and harm-reduction approaches to enhance treatment outcome. Rich anecdotes and clinical pearls illuminate the science, and the book also includes information for special client groups, such as older individuals and those who hoard animals. Printable handouts help busy practitioners. This book is essential reading for clinical psychologists, psychiatrists, psychotherapists, and practitioners who work with older populations, as well as students.