Underestimated, under-researched, and often poorly understood, the body-focused repetitive disorders nevertheless cause human suffering that is serious, persistent, and pervasive. These disorders can occur in both adults and children and manifest themselves as hair pulling (trichotillomania), pathologic skin picking, thumb sucking, and nail biting. Although these disorders are common, very few medical students and residents hear them addressed in lectures or know where to begin when confronted...