Body Dysmorphic Disorder, or BDD, is a mental disorder where an individual is excessively concerned and preoccupied with an imagined or minor defect in their appearance. They may complain of several specific features or a single feature of their appearance, or a vague feature or general appearance. The preoccupation causes them significant psychological distress that impairs important functioning (i.e., occuppational or self-care), or social aspects of their lives.