Attachment theory has been instrumental in identifying insecure disorganized attachment as a developmental pathway that leads to severe psychopathology in adults. Psychotherapy with these patients is challenging, offering a confusing pattern of relatedness, difficulties in mentalizing, problems expressing affect, utilizing dissociative defenses, and trying to gain an understanding of their subjectivity. This article provides a theoretical overview of disorganized attachment focusing on its etiology and how it presents throughout the life span. It reviews important therapeutic guidelines that help navigate the relationship with adults and presents a case study highlighting some clinical challenges.